Restrict build status icon to master branch

tathamoddie · tathamoddie · commit 021794c2b08c · 2017-11-04T13:33:38.000+11:00
Was picking up PR builds otherwise
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-[![AppVeyor](https://ci.appveyor.com/api/projects/status/github/tathamoddie/System.IO.Abstractions?svg=true)](https://ci.appveyor.com/project/tathamoddie/system-io-abstractions)
+[![Build status](https://ci.appveyor.com/api/projects/status/em172apw1v5k70vq/branch/master?svg=true)](https://ci.appveyor.com/project/tathamoddie/system-io-abstractions/branch/master)
 
 Just like System.Web.Abstractions, but for System.IO. Yay for testable IO access!
 

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-[![AppVeyor](https://ci.appveyor.com/api/projects/status/github/tathamoddie/System.IO.Abstractions?svg=true)](https://ci.appveyor.com/project/tathamoddie/system-io-abstractions)`
	`1`	`+[![Build status](https://ci.appveyor.com/api/projects/status/em172apw1v5k70vq/branch/master?svg=true)](https://ci.appveyor.com/project/tathamoddie/system-io-abstractions/branch/master)`
`2`	`2`
`3`	`3`	`Just like System.Web.Abstractions, but for System.IO. Yay for testable IO access!`
`4`	`4`