findBy<ReferenceField>Ids

Finder for arrays of ids generated for all reference fields. Handy for "joins".
fix coding standard
finders for referencesMany fields

These ara analogous to the finders for the referencesOne fields
findById and findByIds in queries
empty generated models for tests
Merge pull request #7 from dripolles/findby

FindbyId, findByIds, and finders for referencesMany