Feature request - Add 'revisions' and 'approval'

(from [5c58259381e5d37720305d835dbbf3d43c1ef478]) Add revisions and approval to text module [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/5c58259381e5d377...

(from [13f24e7b78cf4264098d385c08a354d2ed9ead77]) Shouldn't display revision number if there is only one revision (original) [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/13f24e7b78cf4264...

(from [b01f65b74c594f168cf7e1476fdd29a58960c82c]) Adds 'approval' feature (currently only text showall action/view) [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/b01f65b74c594f16...

(from [3cf2b2520ded067d2c9adc5104dd44bdd51078c6]) Fixes 'Preview mode' to account for un-approved items by only displaying approved revisions [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/3cf2b2520ded067d...

(from [1cf7a23267eef168d1d6ba2dd6039e754da206d8]) Restricts 'Approve' action to 'edit' perm...if you can't edit it, you can't approve it...e.g., if you can only create/edit your own items, you must not be allowed to 'approve' other items, nor should we default to allowing you to approve your own items unless granted permission. [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/1cf7a23267eef168...

(from [17563a4bbb9a3a54036aee231ea437a63ea80593]) Adds 'editor' field to all tables with 'edited_at' field for consistency with upcoming revision support; displays 'editor' of revision in revisions list [#1058 Feature request - Add 'revisions' and 'approval'] https://github.com/exponentcms/exponent-cms/commit/17563a4bbb9a3a54...