Change the install URI in the check
Further refinement
Remove php_flag line, it may cause errors in some environments, add it locally if necessary
Restructure how the defines are loaded

The code to allow custom defines never actually attempted to load custom defines.php files, modified this to actually do so.  In accomplishing this, the version define needed to be moved so it would always be defined by us.  The updated defines codes enables the code to be symlinked to different locations, but there's some cleanup necessary to accomplish this.
Don't move the install folder after installation, we check for this in the src/boot.php file
Remove references to non-existant media and an unused helper class
Add a top level media folder, intent is to refactor all uses of src/Cobalt/media to use this instead
Reset all filesystem permissions to the proper 755/644 values for folders/files respectively
Merge remote-tracking branch 'upstream/staging' into staging