Install readline-devel on CentOS

  * enables libpq to be compiled [#54322628]

Signed-off-by: Brian Cunnie <cunnie@pivotallabs.com>
Install sudo on CentOS

  * add serverspec in both centos and ubuntu
    * even though the latter installs sudo implicitly

[#54322628]

Signed-off-by: Brian Cunnie <cunnie@pivotallabs.com>
Configure sudo on CentOS

  * backfill serverspec for ubuntu

[#54322628]

Signed-off-by: Brian Cunnie <cunnie@pivotallabs.com>