Merge branch 'master' of github.com:cboursnell/transrate into cboursnell-master

Conflicts:
	lib/transrate/assembly.rb
	lib/transrate/comparative_metrics.rb
wip
replaced inline C with C extension
added tests to check dibase composition
fixed tests
removed mocking classes; not needed now
require compiled c library
remove inline requirement
fix for possible null byte in input sequence
new test to check null byte in sequence doesn't cause errors
gsub doesn't work on bio::fastaformat, but does on bio::sequence
remove inline requirement
removed duplicate 'should'
added crb-blast minor version
bumped required crb-blast to version 0.3.1
new test task for contig.rb
changed names of metrics to match docs
add split arguement to crb-blast run method
fix contig gc and at skew calculations and tests
add test to check linguistic complexity over long sequences