#18 Site settings: added new tabs; fixed rendering of dates;
#18 Changed formatting of returning saved page dates
#18 Image selection logics in edit blog form
#18 Refactored pages table: added reference to Image, removed ImageUrl
Merge remote-tracking branch 'remotes/origin/dev' into dev-blogs
#18 Fixed rendering of blog post image
#18 Created JS view model for handling blog tags logic
#18 Implemented save / getting of blog tags list; refactored getting of page tags list;
#19 Editable grid modifications: templates, view models, js; + using editable grid in blog -> authors
#18 Finished editable grid inline editor saving
#18 Created template for selecting image in the authors grid
#18 Authors: refactored table, modified get / save commands; created view model with image;
#18 Finished logics of selecting an image for an author in the grid;
#18 Browsing image for author javascript modifications
#18 Created required attribute extender;
#18 Fixed handling of escape and enter keys;
#18 Error class is applied only for not-new items
#18 Restoring old picture, when canceling author editing;
#18 Editable grid javascript view model: some virtual methods changed to not-overridable
#18 Created options table in blogs module, save and get commands for default template id, option controller