.htaccess: File concatenation requires mod_include
.htaccess: Extend the list of forbidden files

Add Emacs auto-save files (http://emacswiki.org/emacs/AutoSave) and
vim swap files (http://vimdoc.sourceforge.net/htmldoc/recover.html)
to the list of forbidden files.

Thanks @feross and @awebdeveloper.
.htaccess: Add Content Security Policy boilerplate
.htaccess: AddCharset & AddType require mod_mime

Documentation: http://httpd.apache.org/docs/current/mod/mod_mime.html
Merge remote-tracking branch 'refs/remotes/origin/master' into mr.hyde