Change remove_all_dcc_binds() so that it only removes DCC binds for the module supplied, as it's supposed to.
get_dcc_type() should ignore the first entry in dcc_types[] ("<none>") otherwise the client will try to
respond to DCC requests with that name.
Explicitly track the number of entries in the dcc_types[] array rather than using a NULL terminator. This
allows us to change dcc_types[] to use NULL entries to mark unused slots in the array, rather than pointers
to entries with a NULL .name element. Together, this means that the dcc_types[] array is only resized when it
actually needs to be grown and removal works correctly (without eg. prematurely marking the end of the array).
Make add_dcc_bind() fail if the requested DCC type has already been bound by a module (this still allows one
module at a time to rebind a built-in DCC type). Previously the behaviour was ill-defined in this case.
9e7fc85ae1