Fix apt key not being a key

This prevents the key from being constantly re-added everytime puppet is run
due to apt not detecting that the key is already present.
Merge pull request #32 from johnnyg/fix-apt-key

Fix apt key not being a key
add missing Exec resource path attribute
Merge pull request #62 from nagas/fix/curl-exec-path

add missing Exec resource path attribute
add @ to all puppet variables referenced in templates to remove deprecation warnings
Merge pull request #64 from nagas/fix/templates/ruby-instance-variable-syntax

add @ to all puppet variables referenced in templates to remove deprecat...