Swap algorithms test

Trying to find out which algirithm for memory swapping in c is the fastest.

Tested: xor swap algorithm and temporary variable algorithm in 3 slightly different variants.

For the results see report.md and report_inline.md for result with inlining.

To run your test use script swap_test.sh. INLINE variable controlls whether to inline algorithms.

In summary tmp3 algorithm inlined seems the best option.