Issues #1214616 and #1156564: Taxonomy term translation issues and Remove term from translation set when language is set to none.

Fixed issues with taxonomy translation, reimplementing with object translation and advanced caching.

Issue #1159912: Fixed sync not working with term references. Improved field sync callbacks, to be more field API like.

Issue #1165962: Generalize translation sets. Reimplemented taxonomy translation set overview, added set delete

Issue #1157484 by das-peter | skilip: Fixed Both delete translation sets when deleting a menu and when deleting menu items.

Issue #1157456 by skilip: Changed Remove the  'Language neutral' option when translation mode is set to I18N_MODE_LANGUAGE.

Issue #1157382 by skilip, dereine and myself: Improve and unify multilingual descriptions on vocabulary and menu forms

Issue #1070256 by idflood, webflo | teslegch: Fixed Localize terms show always the default language.

Issue #1157456 by skilip: Remove the 'Language neutral' option when translation mode is set to I18N_MODE_LANGUAGE

Issue #1157458 by dereine: Fixed Taxonomy description is not translated on the taxonomy node listing.

Jose Antonio Reyero del Prado authored May 13, 2011 and Florian Weber committed May 13, 2011

Issue #1156560 by skilip: Both delete translation sets when deleting a vocabulary and when deleting terms

Issue #1156560 by skilip: Both delete translation sets when deleting a vocabulary and when deleting terms

Followup to #1155238 by Gábor Hojtsy: add translate tab on vocabulary and move the translation set feature around, so that it sits with the term list, not to confuse users

Follow up to #1155238 by Gábor Hojtsy: add translation tab support for localizable terms using our general tools in i18n_string module

Issue #1075950: Fixed vocabulary language option. Added shared form to select i18n_mode and language.