Includes instructions on how to get an updated GCC on CentOS 6, which
otherwise has GCC 4.4. These instructions will need to be expanded for
devs working on Orca.

README.CentOS.bash automates dependency installation.

Recommend sourcing devtoolset-6 in CentOS dev setup instructions
Signed-off-by: NNikhil Kak <nkak@pivotal.io>
Signed-off-by: NAmil Khanzada <akhanzada@pivotal.io>
Signed-off-by: NBen Christel <bchristel@pivotal.io>