LB-814: Image post does allow comments to be added in a wrong place

Move image before contenteditable on render and
put it back into content on save.
Merge pull request #291 from petrjasek/lb-814-image-comments

Lb 814 image comments
LB-861: On embed -> user comment, if the first filled captcha text is incorect later it will not accept it even if the correct text is provided

Build made.