getters; return proper format for GIFs

lib/getters.js

@@ -22,7 +22,7 @@ module.exports = function (gm) {
    */
 
   var map = {
-      'format': { key: 'format', format: '%m' }
+      'format': { key: 'format', format: '%m ', helper: 'Format' }
     , 'depth':  { key: 'depth',  format: '%q' }
     , 'filesize': { key: 'Filesize', format: '%b' }
     , 'size':  { key: 'size', format: '%wx%h ', helper: 'Geometry' }

test/getterFormatGIF.js

@@ -0,0 +1,17 @@
+
+var assert = require('assert');
+
+module.exports = function (_, dir, finish, gm) {
+  if (!gm.integration)
+    return finish();
+
+  gm(dir + '/original.gif')
+  .format(function (err, type) {
+    if (err) return finish(err);
+
+    assert.equal(type, 'GIF');
+    assert.equal(this.data.format, 'GIF');
+
+    finish();
+  })
+}