Merge branch 'release/0.9.0' into develop
Uri extension set for specific types only rather than all
Removed old unused `processString` method
Update Markdown.php
Merge pull request #37 from ghLoser/patch-2

Update Markdown.php - Looks good! thanks.
Moved Browser class into its proper location
Some changes to make custom template object instantiation to work
Added method to check for changes by file rather than by folder, made it default option as its safest
Forgot to return the last_modified timestamp, and some cleanup
just a variable name change
Fix some misc bugs for admin plugin
Add theme:/// to be able to refer all the themes
Fix theme thumbnail urls
Added Content-Length header
Should address issue #38 where some people are not getting cache clears
Revert "Added Content-Length header"

This reverts commit a737cfc2ec1f5873a50df2821c88c18bc0f22117.
Added updated minify package with fix for @supports, vendor commits and cleanup
Added support for relative links and actual path links to markdown links
Added support for absolute path images and refactored a little
Updated README with some more core feature links