Add 'strict' mode to equivalence Episode filtering

Configure Episode equivalence filtering with a strict mode flag. In
strict mode an Item's candidate equivalent's Container must be
equivalent to the Item's Container. That is, for a candiate equivalent,
E, of item, I, E's Container, Ec, must be equivalent to I's Container,
Ic. In relaxed mode, Ec need not be equivalent to Ic but there must be
no other equivalent container for that source.

Currently all filters are in relaxed mode
Add ContentEquivalenceUpdater.Builder, refactor EquivModule to use it
Rename ItemScoreFilteringCombiner, refactor ScoreThreshold
VOD Equivalence Item require Title Score
add MediaType filter
Rename Scorers that end EquivalenceScorer
Remove RequiredScoreFilteringCombiner from standard Item updater

The RequiredScoreFilteringCombiner in the standard Item Equivalence
updater referred to a generator that was only used for Container
equivalence.
correct guava Ranges import
VOD Containers require a Title Equivalence score
Add comment to EpisodeFilteringEquivalenceResultHandler
Merge pull request #216 from atlasapi/mbst-4081-strict-parent-episode-filter

VOD Sources Equivalence Updates