Implement first thread spawner version.

Compiles to decent RTL. Tests does not pass.
Rename and tweak thread spawner
Fix errors in thread spawner test bench
Fix thread spawners for thread numbers i*barrel_height*num_sp
Fix tb, and cleanup
Test ALU testing.
Merge pull request #30 from dmpro2014/thread_spawner_impl

Thread spawner impl
Add decode support for add immediate
Merge pull request #31 from dmpro2014/decode_fix

Add decode support for add immediate
Finish ALU test, implement XOR
Improve constants file
Fix broken testbenches
Merge pull request #32 from dmpro2014/add-alu-test

ok
Merge pull request #29 from dmpro2014/improve-constants-file

Improve constants file
Merge branch 'master' into lsu-simple

Conflicts:
	vhdl.xise