also make the RIOT_VERSION variable available in buildtest

Building MSP boards gives an error, because `VERSION` is somewhere
defined in their toolchain as an integer.

This PR renames `VERSION` into `RIOT_VERSION`, because that's what it
is.

make automatically adds '-Wl,' to linker-options. Supply `LINKFLAGPREFIX :=` to avoid that.

Changed RIOT/Makefile.include, Makefile.base, Makefile.cflags, and native/Makefile.include to compile C and C++ files.

Fixes issue #1333.

Almost everything was build sequentially in RIOT, because we employed
explicit for-loops to build directories (DIRS). This PR makes our make
system use normal dependencies to build directories.

All our compiling rules were duplicated, once for the application, once
for modules. This PR makes the application a normal module, removing
this duplication.

fixes https://github.com/RIOT-OS/RIOT/issues/1284

fixes #548

Currently most blacklistings for examples and tests are done because the
board provides too little RAM or ROM. Besides of the actual linking all
the compiling should nevertheless work just fine.

This PR adds the variable `BOARD_INSUFFICIENT_RAM` to tell the
`buildtest` to compile the code for a board, but omit the linking step.

Remove some outdated example code.

Sometimes it is difficult to track down build errors for boards that you
are unfamiliar with.

This change adds `make buildinfo` that prints out all the relevant build
information for the selected board and project:

```
PROJECT: default
BOARD:   msba2
CPU:     lpc2387
MCU:     lpc2387

RIOTBASE:  /home/kijewski/RIOT/RIOT
RIOTBOARD: /home/kijewski/RIOT/RIOT/boards
RIOTCPU:   /home/kijewski/RIOT/RIOT/cpu

DEFAULT_MODULE: auto_init core cpu sys
DISABLE_MODULE:
USEMODULE:      arm_common cc110x_ng cc110x_spi config defaulttransceiver gpioint lib lpc_common ltc4150 mci net_help posix protocol_multiplex ps random rtc shell shell_commands sht11 timex transceiver uart0 vtimer

ELFFILE: /home/kijewski/RIOT/RIOT/examples/default/bin/msba2/default.elf
HEXFILE: /home/kijewski/RIOT/RIOT/examples/default/bin/msba2/default.hex

CC: arm-none-eabi-gcc
CFLAGSS:
        -DBOARD_MSBA2
        -DCPU_LPC2387
        -DMODULE_ARM_COMMON
        -DMODULE_AUTO_INIT
        -DMODULE_CC110X_NG
        -DMODULE_CC110X_SPI
        -DMODULE_CONFIG
        -DMODULE_CORE
        -DMODULE_CPU
        -DMODULE_DEFAULTTRANSCEIVER
        -DMODULE_GPIOINT
        -DMODULE_LIB
        -DMODULE_LPC_COMMON
        -DMODULE_LTC4150
        -DMODULE_MCI
        -DMODULE_NET_HELP
        -DMODULE_POSIX
        -DMODULE_PROTOCOL_MULTIPLEX
        -DMODULE_PS
        -DMODULE_RANDOM
        -DMODULE_RTC
        -DMODULE_SHELL
        -DMODULE_SHELL_COMMANDS
        -DMODULE_SHT11
        -DMODULE_SYS
        -DMODULE_TIMEX
        -DMODULE_TRANSCEIVER
        -DMODULE_UART0
        -DMODULE_VTIMER
        -O2
        -Wall
        -Wstrict-prototypes
        -mcpu=arm7tdmi-s
        -gdwarf-2
        -std=gnu99
        -fno-delete-null-pointer-checks
        -Wstrict-prototypes
        -Werror=strict-prototypes
        -Wold-style-definition
        -Werror=old-style-definition

LINK: arm-none-eabi-gcc
LINKFLAGS:
        -gdwarf-2
        -mcpu=arm7tdmi-s
        -static
        -lgcc
        -nostartfiles
        -T/home/kijewski/RIOT/RIOT/cpu/lpc2387/linkerscript.x

OBJCOPY: arm-none-eabi-objcopy
OFLAGS:  -O ihex

FLASHER: lpc2k_pgm
FFLAGS:  /dev/ttyUSB0 /home/kijewski/RIOT/RIOT/examples/default/bin/msba2/default.hex

TERMPROG: /home/kijewski/RIOT/RIOT/dist/tools/pyterm/pyterm.py
PORT:     /dev/ttyUSB0

DEBUGGER:
DEBUGGER_FLAGS:

MAKEFILE_LIST:
        /home/kijewski/RIOT/RIOT/examples/default/Makefile
        /home/kijewski/RIOT/RIOT/Makefile.include
        /home/kijewski/RIOT/RIOT/Makefile.modules
        /home/kijewski/RIOT/RIOT/Makefile.pseudomodules
        /home/kijewski/RIOT/RIOT/Makefile.defaultmodules
        /home/kijewski/RIOT/RIOT/boards/msba2/Makefile.include
        /home/kijewski/RIOT/RIOT/boards/msba2-common/Makefile.include
        /home/kijewski/RIOT/RIOT/boards/msba2-common/Makefile.dep
        /home/kijewski/RIOT/RIOT/cpu/lpc2387/Makefile.include
        /home/kijewski/RIOT/RIOT/cpu/arm_common/Makefile.include
        /home/kijewski/RIOT/RIOT/cpu/lpc_common/Makefile.include
        /home/kijewski/RIOT/RIOT/Makefile.dep
        /home/kijewski/RIOT/RIOT/Makefile.cflags
        /home/kijewski/RIOT/RIOT/sys/Makefile.include
        /home/kijewski/RIOT/RIOT/drivers/Makefile.include
        /home/kijewski/RIOT/RIOT/Makefile.buildtests
```

Partial revert of 85b7eca1

Fixes #1197.

Fixes #1104, alternative to #1178.

`Makefile.include` is too long as is.

Closes #993.

We do not need to descend into the modules to know what to do on
`make clean BOARD=blub`. We can just invoke `rm -rf bin/blub`.

This PR only keeps the descending into the USEPKGs, since they might
want to delete cached/downloaded/extracted data.

Closes #926

Application developers use `$(USEMODULES)` in their Makefiles to have
the relevant functionally automagically added to their apps. This even
does basic dependency tracking by means of `Makefile.dep`.

But an important thing is missing: the automatic adding of include
paths. This is inconvenient, error prone, and will hinder the RIOT core
developers in future to change folder structures.

addresses https://github.com/RIOT-OS/RIOT/pull/883#issuecomment-37833467

Display all stderr output but suppress warnings.

implements https://github.com/RIOT-OS/RIOT/issues/835

Add `|| exit 1` to all constructs like `@for i in $(DIRS) ; do "$(MAKE)" -C $$i ; done ;`, so that compilation stops on the first error.