add form preview
Merge pull request #218 from lampslave/master

add form preview
fix markdown preview
fix markdown version
fix articles and news display, fix #216
fix requirements
remove old packages
Move Django 1.4.7 -> 1.4.8.
Add responsible into forum templates
Forum index is responsibled.
Make other pages responsibled.
Change markitup to pagedown.
Fix submit button.
Fix constructor arguments.
Make edit form similar to add form.
Fix templates.
Коррекция инструкции.
Инструкция по работе с GIT.
Move Sentry settings to production configuration.
Revert "Move Sentry settings to production configuration."

This reverts commit 5ed075a9938bd2c839d18dd12362d1e57f961be7.