categorize_package now returns score and reasons
Have categorize_package2 for new functionality to avoid breakage
[1599] Auto-theme in package form - add tests for categorize_package(2).
Make failing test pass
[1599] Auto-theme in package form - More testing. Fix theming by function.
Merge pull request #73 from datagovuk/return-theme-reasons

categorize_package now returns score and reasons