ENH: sanity check qual scores
API: force_phred_offset -> phred_offset, DOC: changed error message on qual check
ENH: formatter accepts other phred offsets
MAINT: fastq is astronomically stupid
BUG: default offset changed, fixed
MAINT: removed unused import
STY: numpydoc adjustments, thanks @gregcaporaso
Merge pull request #282 from wasade/remove_casava_check

ENH: sanity check qual scores
Merge branch 'master' into py3

Conflicts:
	skbio/format/fastq.py
	skbio/format/tests/test_fastq.py