Tweak: Made a function static
Save a few Kb code size
Relax the typing a bit, and add a missing integer sign check.
Backend: unhook_fd_callback_box() now also unlinks.

Active fd boxes that were destructed could potentially have their
next link zapped, which would break the cyclic list and drop the
following fd boxes on the floor, and not having them get added to
the active fd_list any more.

Potential fix for backend stopping notifications on some long time
fds, and starting to eat 100% cpu.
Fixed extension values for self signed certificates.
Incompatible change for multibyte get/put_var_uint_array ADT.struct calles. The SSL specification, which is was made for, stores the number of bytes in the array size description, while this implementation stored the number of elements. Either one works fine for 1 byte arrays, which this was used for. Changed to use the byte size.
Use get/put_var_uint_array for multibyte uints where possible.
Crypto.DH: Added the groups from draft-gillmor-tls-negotiated-dl-dhe-02

This adds some Diffie-Hellman parameter groups intended for the
DL-DHE TLS extension in the above draft.
Testsuite: Added test vectors for AES-CTR from RFC 3686.