Update checking now occurs when using command-line tools if no check has occurred in the last 24 hours.
- Users who don't use hosted mode should now be aware when GWT is updated.
- An update notifaction will only be emitted on a successful compile
- Update checking now uses TreeLogger's HelpInfo so that users are no longer confronted with modal dialog.
- -XdisableUpdateCheck is added to the command line tools so that, for example, build systems behind firewalls can opt-out.

Patch by: jat
Review by: me


git-svn-id: https://google-web-toolkit.googlecode.com/svn/releases/1.6@4524 8db76d5a-ed1c-0410-87a9-c151d255dfc7
16 files changed