Merge pull request librosa#309 from bmcfee/release-042 Preparing for release 0.4.2

updated version to 0.4.1 final 

Merge pull request librosa#264 from bmcfee/documentation-041 Documentation updates in preparation for 0.4.1

redirected documentation to point at pythonhosted.org 

Merge pull request librosa#193 from bmcfee/develop Merging toward 0.4rc2

travis is no fun at all, still hacking dependencies 

added license to changelog 

updated docs install guide 

lowered the default memory limit 

pointing nbviewer to the new demo