Merge pull request #272 from emorency/feature/OPAL-1928-categories-edit-ui

OPAL-1928: Categories Editor UI. MoveUp/Down and locales from table locales
OPAL-1928: Support edition of categories of views variable
OPAL-1981: Resolved issue by recreating a dto to save
OPAL-1981: Resolved issue by recreating a dto to save
OPAL-1931: Variable Properties editor modal window
OPAL-1931: Variable Properties editor modal window