[IMP] SASS support, dependency fetching

 * Fetch asset dependencies - currently for jQuery, Compass and qTip2
[IMP] Replace generate.sh with fab task
[IMP] Added env vars, pythonbrew check/install
[IMP] Added fab task to generate docs

 * Gets run on tarball generation time
[IMP] Compass files properly loaded
[IMP] Improvements in fabfile

 * File delete confirmation;
 * Option to use system nodejs;
 * cleanup task;
[FIX] 'uiTabs' -> 'ui-tabs'
[IMP] Installing underscore with setup_deps
[FIX] Use webassets for git, because of PySCSS plugin

 * Fix not available in official release;
[IMP] Create all minified files in /static/assets

 * Instead of having them spread across htdocs;
[FIX] 'uiTabs' -> 'ui-tabs'