Added a check for the php config databag, creates if it doens't exist.
Moved pear perms fix so that it only runs on the active version.
Updated slowlog variable to non-deprecated version.

Looks like mariadb 10 removed the old one.
Add missing homebrew/versions tap.
Removed old php and xhprof cookbooks.
Removed custom formulas.
Removed formula copying.
Added basic validation for php-switch.
Added initial test for php-switch validation.