HUE-8740 [librdbms] Make the build of dbproxy.jar optional
HUE-8740 [librdbms] Make the build of dbproxy.jar optional

cloudera/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue,kawamon/hue,kawamon/hue,kawamon/hue,cloudera/hue,kawamon/hue,cloudera/hue,kawamon/hue,kawamon/hue,kawamon/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue,cloudera/hue,cloudera/hue,kawamon/hue,cloudera/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue,kawamon/hue,cloudera/hue