Provides functions for type 3, 4 and 5 UUID generations.

UUID type 1 is timestamp based and requires an accurate time source. For
this reason it is left out of this implementation. UUID type 2 is not
defined in RFC 4122 and thus also not included here

- Cleanup package makefile.
- Download directly from git.
- Remove giant patch.
- Implement malloc function as a contrib package.
- Update ccn example.
- Update ps command.

The msg_time member is only locally used and set before read. It can
be removed as the state kept by the member is not used.

Reordered struct members to not waste memory due to padding.

Before:
``` C
typedef struct {
    uint8_t src_l2addr_len;
    uint8_t dst_l2addr_len;
    kernel_pid_t if_pid;    // <-- 16 bit, is aligned to 16 bit
    uint8_t flags;
    uint8_t __padding_byte; // <-- Inserted to fulfill padding requirements
    int16_t rssi;           // <-- 16 bit, is NOT aligned to 16 bit
    uint8_t lqi;
    uint8_t __padding_byte2;// <-- Inserted to fulfill padding requirements
} gnrc_netif_hdr_t;
```

Now:
``` C
typedef struct {
    uint8_t src_l2addr_len;
    uint8_t dst_l2addr_len;
    kernel_pid_t if_pid;    // <-- 16 bit, is aligned to 16 bit
    uint8_t flags;
    uint8_t lqi;
    int16_t rssi;           // <-- 16 bit, is aligned to 16 bit
} gnrc_netif_hdr_t;
```

When build for the `bluepill` board, the new layout reduces the size by 2 bytes.

PRIu8 is not supported on samr21-xpro:

    type:   hu  code:   hu

After fix

    type: 133  code:   0

Found by running 'tests/gnrc_netif'

Function is broken with num_bytes >= 4.

Could happen when storing input_len with len_encoding >= 4.
It can take values from 2 to 8, so make it work for cases it would overflow.

Refactorg checking that length can be stored in a number of bytes to a
subfunction.

Maximum input_len depends only on length_encoding and not auth_data_len.
The current length_max value was also wrong.

RFC3610 page 2

   3. The message m, consisting of a string of l(m) octets where 0 <=
      l(m) < 2^(8L).  The length restriction ensures that l(m) can be
      encoded in a field of L octets.

The "new" forwarding table does not update an old route but just adds
another as long as it is not *exactly* the same. However, the RPL
adaptation missed to remove the old route so RPL got easily confused
about where it actually needed to send packets.

Follow up to #9067 and part of #8821

Prevents conflicts when multiple modules/packages provide a `cbor.h`
header.

Change the API to use int32_t instead of int, to allow for greater
flexibility on 8- and 16-bit platforms. Removed limitation on input
arguments that min < max. Times where it can be useful to have min > max
is when measuring a sensor where a higher measured voltage means a lower
physical value. For example a thermistor can be connected so that the
measured voltage goes down when the temperature goes up.