func RegisterIssueHandler(name string, fn IssueHandler, help HelpProvider) {
	pluginHelp[name] = help
	issueHandlers[name] = fn
}
func RegisterIssueHandler(name string, fn IssueHandler, help HelpProvider) {
	pluginHelp[name] = help
	issueHandlers[name] = fn
}
// RegisterIssueHandler registers a plugin's github.IssueEvent handler.