compass 6.x-1.0-beta3

Many bug fixes, notably compatibility with latest versions of Compass.

• clear css cache when recompiling with compass.
• remove dependency on devel module.
• when the theme cache is reset, also regenerate the CSS by running _compass_update().
• upgrade to compass 0.10.0 command syntax.
• enable constant recompilation in coordination with devel module's theme rebuild.
• refactor execution functions.
• move pages and admin settings to include files.
• fix all strict coder warnings.
• move submit and validate functions into include files.
• i18n fix on page title.
• crude drush integration.
• fix cron task.
• separate helper functions into include file.
• expose compass_devel_rebuild in admin settings form.
• delete variables on uninstall.
• #870924: Incorrect relative-assets by ckng: Incorrect relative-assets
• add drush validation hook.
• drush compile only displays output for verbose requests.
• refactor option string function.
• #919032: hook_menu_link_alter doesn't take $menu as a reference by seutje: hook_menu_link_alter doesn't take $menu as a reference
• add gem path and gem home variables.
• improve code style and comments.
• use new method to determine shell path.
• simplify shell exec function.
• handle possibility that current theme is not a sass enabled theme.