Continuous Integration Setup & Code Cleanup

Tech debt release to get CI working, catch up on some unit tests, documentation, etc.

Refactoring (Could Impact Existing Code)

• Changed NebulaSettings.cls to use static variables and methods
• Changed Logger.cls to use static methods - everything now calls Logger directly
• Renamed QueryUtils.cls to QueryArgumentFormatter.cls (and refactored it)
• QueryBuilder.cls now uses QueryArgumentFormatter.cls
• Fixed the ordering of the filter scopes to be in descending order (for readability)

Bugfixes

• Fixed a problem with SObjectRecordTypes.cls when the object has no record types
• Logger now checks the custom setting to see if it is enabled

Continuous Integration

• Added .travis.yml for continuous integration. Passing unit tests with 75% code coverage is now required to approve a PR
• Added Travis CI build badges to README.md

Unit Tests

• Standardised the naming convention on a few test methods
• Added more unit tests & test classes