Update NOTICE.txt
Update NOTICE.txt

- Add new dependencies (electron-log, electron-updater, and semver)
- Remove unused dependency electron-squirrel-startup
- Misc homepage and project info updates

mattermost/desktop,mattermost/desktop,yuya-oc/desktop,mattermost/desktop,yuya-oc/desktop,yuya-oc/electron-mattermost,yuya-oc/electron-mattermost,yuya-oc/desktop,mattermost/desktop,yuya-oc/electron-mattermost,mattermost/desktop