update_versions to add version 6 apps.
It looks for API_VERSION string in main executable,
adds the API version to the app_version XML,
and sets min_core_version to 6 for version 6+ apps
- API: include API_VERSION string
- convert tabs to spaces here and there
- scheduler: parse unused elements in <net_stats>
- ops/show_log.php: if no URL args, just show form (fixes#415)
- client: parse and store api_version (not used yet)
svn path=/trunk/boinc/; revision=13627