parse single quote strings just as double strings and add some sanity checks to parsing brace levels
parse single quote strings just as double strings and add some sanity checks to parsing brace levels

git-svn-id: f2acecaac6fbd5a03f3d4799db58dda434111981@10152 3eda493b-6a19-0410-b2e0-ec8ea4dd8fda

pscedu/pfl,pscedu/pfl,pscedu/pfl,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/pfl,pscedu/slash2-stable