Warn if the index is older than the fasta/fastq file.
Merge pull request #6 from tomoakin/warn_old_index

Warn if an index file is older than the corresponding fasta/fastq file.
fatt.cc: IMP: small refactoring
FIX: fatt stat outputs a more friendly error message when files cannot be opened
ADD: fatt stat --excn option
ADD: fatt split --max
ADD: fatt len --name
Merge branch 'master' of github.com:mkasa/klab
FIX: format typo
ADD: fatt composition takes --countends option
Merge branch 'master' of github.com:mkasa/klab