Fixed Travis CI
Removed cli require. CLI should be required only as part of the CLI
Removed fixed date and rubygems version from gemspec.
Version bump
Merge pull request #158 from gooddata/0_6_3_release

0 6 3 release
Added better validation to the model
Merge pull request #139 from fluke777/validate

Added better validation to the model
Merge branch 'master' into downloaders_changes
cop fascism fixes