Erweiterung für BLAS Level 3.

- Bisheriges Verzeichnis level1/ verschoben in src/level1.
- Referenz-Implementierung von dgemm in src/level3 und Stubs für den Rest
- BLAS Level 3 Funktionen müssen xerbla aufrufen.  xerbla ist in src/auxiliary
- Makefile in src/ so angepasst, dass ausgewählte Unterverzeichnisse berücksichtigt werden
- In test/ und bench/ wird jetzt auch BLAS Level 3 getestet
Blocked gemm with a *bad* pack method.  So students will see a negative impact on performance related to cache sizes.
Juste removed the C99 crap (restrict keyword).  We still have the *bad* pack
simple variant of packing following the elements with stride 1
We are achieving 96% performance of OpenBLAS!
Ugly but fasr
Cleanup:  Micro kernel can be selected by defining macros.  See src/Makefile
Merge branch 'master' of github.com:michael-lehn/ulmBLAS
Bugfix
Cleanup:  internal functions are now static (i.e. only locally available)
Added support for matrix-matrix products of type A^T*B, A*B^T and A^T*B^T.
Added some comments ...
Cleanup, minor bugfix.
Removed (in this case useless/unnecessary) optimization flags.
Added the license file
Added gnuplot script
Add plot target to makefile, update .gitignore

A plot comparing the performance of the curent branch against refBLAST can now be generated by
make plot

Unfortunately, the y-axis scale is currently fixed - the clean implementation would be to get the peak performance from
/proc/cpuinfo

Some level3 related files and the products of 'make plot' are added to the .gitignore file.

Given the broad use of these changes, I hope for them to be cherry-picked to all level3 implemention branches.

Co-author: Dirk Nille
Fix clean behaviour after make plot
Refine plot script

The script now iterates over all benchmarked branches.
Switch from .png to .svg output