better error report when search => 'string' given

[szabgab]

my $mcpan = MetaCPAN::API->new;
my $module = $mcpan->release( search => 'MetaCPAN::API' );

tells me

Either provide 'distribution', or 'author' and 'release', or 'search' at bin\dependencies.pl line 10.

while the problem is that search needs to get a HASH ref

Also it would be nice to have a few examples of the possible values there.