Add Developer Section / How to Commit from cwiki.apache.org

Reviewers: Attila Simon

This closes #80

dev-docs/HowToCommit.md

@@ -0,0 +1,71 @@
+<!---
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+Apache Flume: How to Commit
+===========================
+
+This guide highlights the process and responsibilities of committers on the Flume project.
+
+**Note**: Just like contributors, committers must follow the same guidelines for contributions as highlighted in the How to Contribute guide.
+
+
+Committing patches
+------------------
+
+The primary responsibility of committers is to commit patches from
+various contributors. In order to do so, a committer should follow these
+guidelines:
+
+-   **Review the patch:** Follow the How to Contribute guide's section on
+    reviewing code to ensure that you review the code before
+    committing it. Every patch that is committed to the source control
+    must be reviewed by at least one committer first. If you are not
+    ready to accept the patch in the current state, make sure you update
+    the JIRA to 'Cancel Patch'.
+
+-   **Make sure patch is attached to the JIRA with license grant**:
+    Before a patch is committed to the source code, the contributor must
+    explicitly attach the patch to the JIRA and grant it the necessary
+    licence for inclusion in Apache works.
+
+-   **Commit the patch:** If the patch meets review expectations and is
+    well tested, it can be committed to the source control. Make sure
+    that the patch applies cleanly to the latest revision and if not,
+    request the patch be rebased accordingly. Once ready for commit, the
+    commit message should have the following format:
+
+    ```
+    Flume-XXX. Brief description of the problem.
+
+    (Contributor's Name via Committer's Name)
+    ```
+
+-   **Mark the JIRA resolved:** After the patch has been committed, you
+    should mark the JIRA resolved and ensure that it's `fixVersion` is
+    set to the next release version number. Make sure to thank the
+    contributor in the comment you add while marking the JIRA resolved.
+
+Contributing patches
+--------------------
+
+The Flume project does not distinguish between committers and
+contributors with respect to contributing patches. Typically, a
+committer submitting a patch will follow the same process as expected
+from a regular contributor and have the reviewing committer checkin the
+submitted change. This procedure is an informal guideline and not a hard
+policy since at times committers may have to bypass the long drawn
+process to commit the change in order to fix a broken build, or work
+through a release etc.