add ID to upload form and check if ID exist to avoid loading invalid javascript code for read-only views.

used get_cfg_var() to get the real limit from php.ini instead of .ht_access
dont know why we used PHP_INT_MAX here...

stripsplashes doesn't work if the slash is the only character -> creating file in root dir leads to "//filename"

check if element really exists before calling it. (e.g. for public shared files view, elements like "navigation" doesn't exist)

automatically remove and prevent installation of apps with a require version less than the current one. We check now the first ad second part of the version number.
Also increase the require tags of the core apps to 4.9 Please note that 4.9 is the internal versionnumber of the upcoming 4.5 release.
You have to pu a <require>4.9</require> into the info.xml of your app to make it as compatible with 4.5

Fixed a strange comment issue

Fix the File Upload Button in Chrome. Tested in IE9-8-7, Firefox, Chrome