Improved the testing suite.

- Each test is now run several times (how many is defined in the code) to get an average execution time.
- Prints the results in to neat colums (Consumed memory (kb) / Exec time (ms))
- Option to choose between endHeap/sbrk and linux statm for calulating used memory. Added this because endHeap was bugged and said no memory was used for best fit for some test cases. This bug just disappeared by itself, though, so there you go.