gpg-interface: handle bool user.signingkey
The config handler for user.signingkey does not check for a boolean value, and thus: git -c user.signingkey tag will segfault. We could fix this and even shorten the code by using git_config_string(). But our set_signing_key() helper is used by other code outside of gpg-interface.c, so we must keep it (and we may as well use it, because unlike git_config_string() it does not leak when we overwrite an old value). Ironically, the handler for gpg.program just below _could_ use git_config_string() but doesn't. But since we're going to touch that in a future patch, we'll leave it alone for now. We will add some whitespace and returns in preparation for adding more config keys, though. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Ben Toews <mastahyeti@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>