Small issues with performance script docs

[hendriks73]

This is regarding https://github.com/JorenSix/Panako/blob/master/resources/scripts/benchmark/benchmark.textile Thank you for adding the script and its description. A couple of minor points:

• Typo in "The FMA medium set contains 25, tracks of 30s spread over 16 unbalanced genres (22 GiB)". "25," tracks seems wrong.
• You show two figures, one for Panako and one for Olaf, but don't describe them at all. Just seeing this one page, it's not easily understandable what Olaf refers to. You might want to add an explanatory sentence, very briefly describing the two graphs and what they show.
• The page describing the benchmark should probably link to the script, instead of just mentioning that it's there.
• The benchmark page does not seem to be linked to (or did I miss it?). A link from the README seems appropriate.

[JorenSix]

Thanks for the feedback!

I have fixed the issues, improved the benchmark script and ran a new benchmark on FMA full (not on 30s but full tracks). The number of seconds indexed is higher which might give some more realistic insights.

Additionally, the benchmark script is linked and the benchmark is described in the main readme.