Show README.md badges for the master branch

Show Travis and AppVeyor badges based on the 'master' branches only.  This way
a build failure on a feature branch (which is likely) doesn't make it look the
like whole project is failing.

README.md

@@ -1,10 +1,10 @@
 # Kintyre's Splunk CONFiguration tool
 
-[![Travis](https://img.shields.io/travis/Kintyre/ksconf.svg)](https://travis-ci.org/Kintyre/ksconf/builds)
+[![Travis](https://img.shields.io/travis/Kintyre/ksconf/master.svg)](https://travis-ci.org/Kintyre/ksconf/builds)
 [![PyPI](https://img.shields.io/pypi/v/kintyre-splunk-conf.svg)](https://pypi.org/project/kintyre-splunk-conf/)
 [![codecov](https://codecov.io/gh/Kintyre/ksconf/branch/master/graph/badge.svg)](https://codecov.io/gh/Kintyre/ksconf)
 [![Coverage Status](https://coveralls.io/repos/github/Kintyre/ksconf/badge.svg?branch=master)](https://coveralls.io/github/Kintyre/ksconf?branch=master)
-[![Windows Build status](https://ci.appveyor.com/api/projects/status/rlbgstkpf17y8nxh?svg=true)](https://ci.appveyor.com/project/lowell80/ksconf)
+[![Windows Build status](https://ci.appveyor.com/api/projects/status/rlbgstkpf17y8nxh/branch/master?svg=true)](https://ci.appveyor.com/project/lowell80/ksconf/branch/master)
 [![Documentation Status](https://readthedocs.org/projects/ksconf/badge/?version=latest)](https://ksconf.readthedocs.io/en/latest/?badge=latest)
 [![PyPI - Python Version](https://img.shields.io/pypi/pyversions/kintyre-splunk-conf.svg)](https://pypi.org/project/kintyre-splunk-conf/)