New MLDonkey release 2.7.6

- Fasttrack, Gnutella & G2 are usable again
- Update default URL for IP blocklist
- Update EDK history HTML links
- Compile with Ocaml 3.09.2
- Filetype recognition with libmagic
- Multiline HTML link input (HTML, DL button)
- New option: pause_new_downloads (reset on startup)