Merge remote-tracking branch 'sokra/source-node-from-string-with-map'
Bumping version number to 0.1.17
Merge remote-tracking branch 'sokra/source-map-gen-apply-map'
Adding a test for github #56
Merge branch 'join-relative-bug'
Bumping version to 0.1.18
use assertEqualMaps
add setSourceContent as method to SourceNode