Refine the Makefile template for unit test

Note that we add a new target named clean-all, which can clean
test-specific files under the current directory. Please overwrite it in
the Makefiles including this file.
Add matrix multiply test
Add test case13
Add test case 14 for struct pointer
Add hanoi test for recursive calls
Refine the matrix multiply test program
Add matrix_multiply-seq code for test
Rename the VERSION to GIRI_VERSION

We may use the VERSION to control sequential or pthread of test cases.
Add VERSION to control the seq or pthread code
Add kmeans test
Add pca test