[SPARKR][MINOR] Update R DESCRIPTION file

## What changes were proposed in this pull request?

Update DESCRIPTION

## How was this patch tested?

Run install and CRAN tests

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #14764 from felixcheung/rpackagedescription.

R/pkg/DESCRIPTION

@@ -3,10 +3,15 @@ Type: Package
 Title: R Frontend for Apache Spark
 Version: 2.0.0
 Date: 2016-07-07
-Author: The Apache Software Foundation
-Maintainer: Shivaram Venkataraman <shivaram@cs.berkeley.edu>
-            Xiangrui Meng <meng@databricks.com>
-            Felix Cheung <felixcheung_m@hotmail.com>
+Authors@R: c(person("Shivaram", "Venkataraman", role = c("aut", "cre"),
+                    email = "shivaram@cs.berkeley.edu"),
+             person("Xiangrui", "Meng", role = "aut",
+                    email = "meng@databricks.com"),
+             person("Felix", "Cheung", role = "aut",
+                    email = "felixcheung@apache.org"),
+             person(family = "The Apache Software Foundation", role = c("aut", "cph")))
+URL: http://www.apache.org/ http://spark.apache.org/
+BugReports: https://issues.apache.org/jira/secure/CreateIssueDetails!init.jspa?pid=12315420&components=12325400&issuetype=4
 Depends:
     R (>= 3.0),
     methods