All server variables such as codeMirrorDir, visibleTabs etc now in
$ICEcoder array
This is so we have a single object to contain all settings, just like
the JS equivalent
Don't need index.php, so removed that
Added extra query string param to list files that should be excluded
from zip
Value of this param is media files (as per list we want to exclude
searching on)
Means you don't end up with long processes and potentially big zips
Now by default the excluded files includes anything in the _coder
folder, plus filetypes that shouldn't really be searched within (mainly
media files).