[PTFM-13697] Skip CentOS 5.11 in applet exec test

Summary:
Skip CentOS 5.11 when remotely running applets in
test_var_initialization, since 5.11's latest official OpenSSL package
is not sufficient for building/linking apps that target Ubuntu 12.04.

Using 'dx build --remote' is the preferred alternative to attempting to
cross-compile C++ apps on old distros that lack up-to-date dxcpp library
dependencies.

Test Plan: Ran test on CentOS 5, OS X 10.9, Ubuntu 12.04

Reviewers: psung

Reviewed By: psung

Subscribers: akislyuk

Differential Revision: https://phabricator.dnanexus.com/D176
Cease building R packages for Debian
Fix condition in c56377b

Print retry success message only when all logic has completed
Fix condition in 88b1d26
Remove import-time side effects from describing job
Revert "WIP"

This reverts commit b154838cd9e5c775a8a2c8a33472819fc764fd6e.
Merge branch 'master' into PTFM-8759-no-import-side-effects

Conflicts:
	src/python/dxpy/__init__.py