repo-group-model: add flag to return proper object along the exported names.

api: refactor auth helpers to reflect the action they do. - those validators verify and throws expcetions, which is now reflected in the name

validation-schema: added StringBoolean type and IPAddr validator.

api-utils: added helper to validate repository-group access permissions.

slugs: make special chars not be replaced by '-'. THis produces a much better slugs. Eg /fo;o/b|ar/ => will be /foo/bar/ and not /fo-o/b-ar/ Which doesn't make sense from human readable names.

backends: fix potential unicode problems on debug logging.

i18n-js: updated generated messages.

i18n: added dummy file wth translations to help extract JS messages from EE version. - helps also to translate parts from unreachable code. Temp solution, but it works.

diffs: add comments to changeset diffs

diffs: add repo_name as parameter of diffset - fixes bug where comparing different target/source repos had wrong diff links