Disable autoupdate completely when setting is "never".
Merge branch 'master' into never_update

* master:
  Add test for the new git config functions.
  Use git's global config to store the crash report configuration.
  Add crash reporting to the readme.
  Remove nesting.
  Check string errors.
  Make gh project info constant.
  Do not modify fatal output.
  Capture panic errors and notify them as unexpected crashes.
  Generate man page for gh
  Add error type to the report.
  Report error, stack and runtime information.
  Move the crash report to the new editor.
  Generate crash report editor message.
  Simplify title and body hint message creation.
  Add github.ReportCrash to send user errors.
Move autoupdate configuration to the global git config.
Merge pull request #172 from jingweno/never_update

Allow to never update.