feature(repository): add getReleases

Closes #320

Author: BernhardBehrendt

lib/Repository.js

@@ -629,6 +629,16 @@ class Repository extends Requestable {
       return this._request('PATCH', `/repos/${this.__fullname}/releases/${id}`, options, cb);
    }
 
+   /**
+    * Get information about all releases
+    * @see https://developer.github.com/v3/repos/releases/#list-releases-for-a-repository
+    * @param {Requestable.callback} cb - will receive the release information
+    * @return {Promise} - the promise for the http request
+    */
+   getReleases(cb) {
+      return this._request('GET', `/repos/${this.__fullname}/releases`, null, cb);
+   }
+
    /**
     * Get information about a release
     * @see https://developer.github.com/v3/repos/releases/#get-a-single-release

test/repository.spec.js

@@ -517,6 +517,13 @@ describe('Repository', function() {
          }));
       });
 
+      it('should read all releases', function(done) {
+         remoteRepo.getReleases(assertSuccessful(done, function(err, releases) {
+            expect(releases).to.be.an.array();
+            done();
+         }));
+      });
+
       it('should read a release', function(done) {
          remoteRepo.getRelease(releaseId, assertSuccessful(done, function(err, release) {
             expect(release).to.have.own('name', releaseName);