Merge branch 'release/2.1.0' into develop
updated changelog
fixed bug with the server shutdown process and improved the exception handling for invalid configuration parameters
Bumped version to 2.1.1 to prepare for release.
Updated rakefile to propperly fetch the previous version for changelog purposes
Updated CHANGELOG.md and gemspec for 2.1.1 release.
Merge branch 'release/2.1.1'