hub 1.12.0

Features:

• hub pull-request -o (--browse) to open the new pull request in the browser
• Support Enterprise over non-secure HTTP via protocol option in ~/.config/hub
• Enable API debug output by setting HUB_VERBOSE environment variable

Bug fixes:

• Fix reusing old OAuth tokens stored in Authorizations API
• Allow help pager to clear screen on exit
• Avoid mispelled pull-request flags getting misinterpreted as title
• Rescue HTTP exceptions during ci-status command