Revert "Another change in exception handling apporach"

This reverts commit 3ee362073fdc3a080a7eee41a300e351f234db08.
Revert "Rename class name to reflect recent changes"

This reverts commit e3c9d82fa3a287f2d9e752088e79261314abb942.
Revert "ruby 2.0.0 compatibility changes"

This reverts commit 77294157e99baab5816f3e36f2341a04ec6ed356.
small code cleanup