Issue #1030970 by loominade: Fixed Terms description not allowed for translation because of its input format.

Cleaning up and making reusable string translation forms. Reworking field translation forms, path was too long for the menu.

Issue #1192332: Fixed Incorrect message on wrong Block translation. Other format handling issues for translation form.

Improved field translations and string handling. String objects are passed around instead of complex data arrays.

Issue #1185644: API improvements. Improved format access checking. Renamed i18n_string_object to i18n_string_object_wrapper

Followup to #1155156 by Gábor Hojtsy: redirect the user back to the translation page, when they save a translation of an object

Issue #1114602 by Gábor Hojtsy, yoroy: improve usability of i18n_string based modules dramatically by providing an API to expose a translation tab on objects
Reference implementation of that on blocks.