Issue 240: Remove Netty dependencies

[shshashwat]

Signed-off-by: Shashwat Sharma shashwat_sharma@dell.com

Change log description
Remove forced netty version from build.gradle causing conflicts with Pravega higher versions

Purpose of the change
fixes #240

How to verify it
The build should pass and all existing test cases should complete successfully

[kotlasaicharanreddy]

LGTM

[shshashwat]

tested both versions of Pravega(0.10.2 and 0.11.0) with this change on live cluster. Performed a few set of operations(creating a schema, editing the schema, deleting the schema) and it worked fine.

[shshashwat]

@tkaitchuck, @sachin-j-joshi, @RaulGracia if you think we are good to go with the changes please take the next action else kindly provide your comment.

[RaulGracia]

Thanks @shshashwat, before merging, please check that building and running Schema Registry samples in Pravega Samples is working fine: https://github.com/pravega/pravega-samples

[shshashwat]

Thanks @shshashwat, before merging, please check that building and running Schema Registry samples in Pravega Samples is working fine: https://github.com/pravega/pravega-samples

@RaulGracia, I tried this also and was able to test them all successfully. Thank you