[pull-request] Fix non-draft pull requests

This works around a GitHub API issue where it blocks PRs based on their
draft status even if they were `draft: false`.

Fixes #2099

commands/pull_request.go

@@ -318,9 +318,12 @@ of text is the title and the rest is the description.`, fullBase, fullHead))
 		pullRequestURL = "PULL_REQUEST_URL"
 	} else {
 		params := map[string]interface{}{
-			"base":  base,
-			"head":  fullHead,
-			"draft": args.Flag.Bool("--draft"),
+			"base": base,
+			"head": fullHead,
+		}
+
+		if args.Flag.Bool("--draft") {
+			params["draft"] = true
 		}
 
 		if title != "" {

features/pull_request.feature

@@ -14,7 +14,7 @@ Feature: hub pull-request
                :body => nil,
                :base => 'master',
                :head => 'mislav:master',
-               :draft => false,
+               :draft => nil,
                :issue => nil
         status 201
         json :html_url => "the://url"