JVMCBC-63: Some updares to the gradle build file.

Motivation
----------
The generated pom file did not add the name and description tags, which
had to be added manually when publishing to maven central.

Modifications
-------------
The following changes have been made:

 - name and description are added
 - sergey and simon added as developers
 - shadow plugin updated to 1.1.2

Change-Id: Ifdb2206c824c639d46a42c2396bbf114d290a23d
Reviewed-on: http://review.couchbase.org/43289
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>