Adds structure for unit testing.

Check MinUnit:
http://www.jera.com/techinfo/jtns/jtn002.html
tests_xgemm.c -> tests.c
Adds the base for testing.
Refines the tester a bit.
Corrects relative difference function.
Adds a new basic test.
Changes minunit output to show progress.
Changes indexes to recognize the tests.
All tests are done with all flags.
Adds tests with random 32x32 matrices.
Outputs the flags in hexadecimal.
Solves a bug with the dimensions on the tester.
Solves spawning when there is no work for them.
Solves a bug inserted in last commit.
Solves a bug inserted in last commit.
Only executes test_tester() once.
Adds a pair more of asserts to the last test.
Adds the needed matrix file for test_sgemm_row().
Adds test_sgemm_row_trans().
Merge branch 'master' into tests