renaming _topbar.less to _header.less
Minor styling updates for detail pages
Searching now filters out any results that aren't Defects, Stories, or Tasks. We don't have renderers for rows or detail pages of other types.
Fixes #21 - Add click-through on US tasks & defects fields to see listing
Minor detail page styling fix
Fixes #22 - Add Markdown support for editing Description field
After logging out from settings page, logging back in would take user to the settings page. Now it takes user to the default page.