refactor(hintLog): update messaging to use HintLog v0.4.0

To use the updated hintLog, each hintLog message should give a severity for that message.
To provide these severities, messages generated via build functions now return arrays
containing severities. The current severities are as follows:
Errors: use of deprecated `replace`, use of mutually exclusive directives, missing
attributes on directives, nonexistent attributes, incompatible attributes
Suggestions: use of appropriate namespaces, use of ngEvent directive in
place of normal event directive.

Closes #30