Support CATKIN_PREFIX_PATH; let CMAKE_PREFIX_PATH come first, so that standard ROS methods still work even if we do not
use them.

Index: ros_environment-1.2.0/env-hooks/1.ros_package_path.sh.em
===================================================================
--- ros_environment-1.2.0.orig/env-hooks/1.ros_package_path.sh.em
+++ ros_environment-1.2.0/env-hooks/1.ros_package_path.sh.em
@@ -4,8 +4,10 @@
 PYTHON_CODE_BUILD_ROS_PACKAGE_PATH=$(cat <<EOF
 from __future__ import print_function
 import os
-env_name = 'CMAKE_PREFIX_PATH'
-paths = [path for path in os.environ[env_name].split(os.pathsep)] if env_name in os.environ and os.environ[env_name] != '' else []
+env_names = [ 'CMAKE_PREFIX_PATH', 'CATKIN_PREFIX_PATH' ]
+paths = []
+for env_name in env_names:
+    paths += [path for path in os.environ[env_name].split(os.pathsep)] if env_name in os.environ and os.environ[env_name] != '' else []
 workspaces = [path for path in paths if os.path.exists(os.path.join(path, '.catkin'))]
 paths = []
 for workspace in workspaces: