fix for remove assignees from issue

The library was assuming that head|get|delete requests don't have a
request body, which isn't the case for endpoints such as
removeAssigneesFromIssue.

Author: Joe Gallo

examples/removeAssigneesFromIssue.js

@@ -0,0 +1,22 @@
+"use strict";
+
+var Client = require("./../lib/index");
+var testAuth = require("./../testAuth.json");
+
+var github = new Client({
+    debug: true
+});
+
+github.authenticate({
+    type: "oauth",
+    token: testAuth["token"]
+});
+
+github.issues.removeAssigneesFromIssue({
+    owner: "kaizensoze",
+    repo: "test2",
+    number: "4",
+    body: { "assignees": ["first9890"] }
+}, function(err, res) {
+    console.log(err, res);
+});

lib/index.js

@@ -612,7 +612,7 @@ var Client = module.exports = function(config) {
         var self = this;
         var method = block.method.toLowerCase();
         var hasFileBody = block.hasFileBody;
-        var hasBody = !hasFileBody && ("head|get|delete".indexOf(method) === -1);
+        var hasBody = !hasFileBody && typeof(msg.body) !== "undefined";
         var format = getRequestFormat.call(this, hasBody, block);
         var obj = getQueryAndUrl(msg, block, format, self.config);
         var query = obj.query;