Bug Fix to Support Http Patch/Put methods

[animo93]

Currently HttpUrlConnection doesn't support Http Patch/Put methods .
There is a Won't Fix bug in OpenJDK for this:
https://bugs.openjdk.java.net/browse/JDK-7016595

So , need to provide a fix along the below stackoverflow solution
https://stackoverflow.com/a/46323891/3647724

[animo93]

I think this issue might already be fixed via #34 . Just need to add test cases and verify