Merge pull request #27 from taliesins/master

Update reference to CFProperty so libxml is not forced upon users of fission fixes #24
switch .rvmrc to .ruby-version/gemset
update CHANGELOG
update CHANGELOG
add rake as a dev dependency
add travis config
fix lease specs which are busted on travis
more lease spec fixes for travis
more lease spec fixes for travis
fix vm lister spec on travis
fix vm lister spec on travis
fix vm spec on travis
add travis badge to README
bump version to 0.5.0.beta.1