module: don't require fs several times

As we are going to need fs in any case, just require it at the
beginning of the file.

Signed-off-by: Fedor Indutny <fedor@indutny.com>
readme: added g++ requirement

Signed-off-by: Fedor Indutny <fedor@indutny.com>
Merge remote-tracking branch 'upstream/master'