This makes several small adjustments to our exposed method names, and in
one case, parameters. The justification here is to make methods less odd
in their naming convention. If a method takes an alpm_db_t argument, the
method should be named 'alpm_db_*', but perhaps more importantly, if it
doesn't take a database as the first parameter, it should not.
All methods keep the same argument list except for alpm_pkg_set_reason;
there we drop the 'handle' argument as it can be retrieved from the
passed in package object.