Fixed stuff

- Fixed the htmlspecialchars problem
- Fixed the ISO -> UTF-8 problem linked to Google.
- Improved random_referer.
- Typo and tabs.
html_entity_decode +fixed cache (doesn't work personally :/)

- Added html_entity_decode on originally ISO encoded Google page to get back the actual UTF-8 characters as it should be. Still don't know why Google doesn't send us UTF-8 directly.
- Effectively grab the thumbnail only if not in cache instead of retrieving it every time.
- Now the cache is based on md5 of the link to avoid risking to get too long file names (256 characters max on some systems).
Fixed the cache (this is working now) + Fixed videos' link

- iconv was messing images up. Previously it was converting binary data (images) too.
-> iconv should only be applied when needed.

- Since I applied html_entity_decode on the previous version, &amp; needed to be remove from the REGEXES (and converted to &)
Merge pull request #24 from JeromeJ/master

I think we're done now