Filter by more extensions/type in file manager

This edit allows to specify more than one value for fType and/or
fExtension.
Youtube url was parsed incorrectly so some type of urls resulted to an incorrect path.
`Type` attribute has been removed and `allowfullscreen` added as suggested by youtube.
`wmode` parameter is removed from iframe url.
`view.php` has been cleaned up.
Avoid detection of private IP addresses

ValidationIpHelper::getRequestIP() scans the following $_SERVER vars:
HTTP_CLIENT_IP, HTTP_X_FORWARDED_FOR, HTTP_X_FORWARDED,
HTTP_X_CLUSTER_CLIENT_IP, HTTP_FORWARDED_FOR, HTTP_FORWARDED,
REMOTE_ADDR (in this order).
If the client is visiting the website via a proxy server located in his
own private network the function may return his local private IP
address.

Let's change this behavior, trying to detect only public IP addresses
(but still returning the private IP address if no public address is
found).
Merge pull request #840 from mlocati/allow-multiple-extension-filter

Filter by more extensions/type in file manager
Merge pull request #1078 from mlocati/fix-ip-detection

Avoid detection of private IP addresses
Merge branch 'fix-refactor/youtube-video-block-embed-urls' of github.com:ojalehto/concrete5 into merge_1059_youtube_url_parsing

Conflicts:
	web/concrete/blocks/youtube/view.php
Convert back to short tags

Convert previous youtube commit back to short tags
Merge pull request #1125 from mkly/merge_1059_youtube_url_parsing

Merge 1059 youtube url parsing