Prepare for release of gem version 1.8.3

Prepare for release of gem version 1.8.2

Prepare for release of gem version 1.8.1.

Prepare for release of gem version 1.8.0.

Prepare for release of gem version 1.7.5.

Prepare for release of gem version 1.7.4

Prepare for release of gem version 1.7.3

Prepare for release of gem version 1.7.2.

Prepare for release of gem version 1.7.1.

Prepare for release of gem version 1.7.0.