Merge pull request #19 from PierreR/master

fix: rename sshauthorizedkey into ssh_authorized_key
Changelog for v0.12.3
Silently ignore source tests for file://
Fix escaping problem in strings
Hacky support for scope.get_hash
to_hash instead of get_hash :)
added puppet as a default user/group
Various new stuff
IsString instances for Expression and UValue
Nicer function signature for getCatalog
Fixed docs
Bump dependencies
typo
Num and Fractional instances for Expression
Fix tests
Properly catch division by 0
tentative solving of floating problems
Internally store numbers as numbers
All is now Scientific internally
First iteration for structured facts support