Upgrade rails in 1.0 upgrade guide
Add notice to fix any deprecation warnings at the end of upgrade guides
Add 1.0 to 1.1 upgrade guide
Fix MD syntax issues in 1.1 release notes
Fix up some typos in the 1.1 upgrade guide
Add 1.1.x -> 1.2.x upgrade guide
Add 1.1.x and 1.2.x upgrade guides to sidebar