add cython
US convention for e.g.
remove space before :
move ref inside the sentence
comments about cython sentence
add points at the end of docstrings
Ubuntu is an example of GNU/linux distrib.
s/4000/5000/ download for March
Merge pull request #14 from sciunto/cython

Mention Cython
Merge pull request #19 from sciunto/ubuntu

Ubuntu is an example of GNU/linux distrib.
Merge pull request #18 from sciunto/docstrings

Remove trailing whitespace
Merge pull request #16 from sciunto/ref

Move reference closer to actual reference
Merge pull request #15 from sciunto/typos

Fix punctuation