Issues #82 #79 #78: refactoring enrollment pdf
Issue #82: City Widget to filter city and state by previous selection of state and country by ajax.
Issue #82: Removed schema_plus, removed all fk from db, added fk validations to models, created tests and matchers for fk validations
Issue #82: Adding birth_city to student and showing birth_city, birth_state, birth_country in transcript
Issue #79: Adding identity expedition place to student
Issue #87: adding city form field to professor,  renaming neighbourhood to neighborhood, adding identity_issuing_place to professor
Issue #88: dependent restrict for all models
Issue #81: Adding thesis defense date to enrollment
Issue #87: identity_issuing_place translation
Issue #78: Addind institution to professor, creating thesis defense comittee, adding committee to transcript
Issue #84: display:none for action links on nested pages
Issue #73: Adding workload to courses and transcript
Merge branch 'enrollment_features'