Add serial console

* 'master' of github.com:/avikivity/osv:
  boot: initialize .bss
  loader: create a JVM
  loader: run an initialization function in libjvm.so
  elf: perform relocations on looked-up symbols
  elf: rename dynamic tag lookkup to dynamic_tag()
  elf: add lookup function to get a fully typed function
  elf: load program as an object, not via a function
  runtime: define environ
  pthread: add pthread_{getspecific,setspecific,key_create}
  mutex: stub implementation
  elf: dump name of symbol which we failed to look up
  runtime: define 'timezone'
  elf: core provides libdl.so functions

Conflicts:
	Makefile