Updated Icrontic's navigation
On desktop only:
- Removed the top right navigation.
- Added the "Me Module" in the sidebar.
- "Mark All Viewed" is now under the gear icon in the Me Module. It works.
- "Mark Category Viewed" now joins it as a "new" option when viewing a discussion or its category.
- Themed the "New Discussion" button and discussion options cog correctly for the dark theme.