growlnotify: experimental formula for 2.0 using pkg installer
growlnotify: improve formula
- make it a keg-only formula
- `chomp` filepaths to avoid extra '\n'
- simplify `installed_files` method with `map` and `flatten`
- use `safe_system` call for package installer
- keep list of files installed in a separate `files.txt` for easy scriptability
- other verbiage changes
java-sdk: formula for 1.7.0_25 using pkg installer
Use `pgkutils` to detect files installed via pkg installer (instead of reading raw receipts)
growlnotify: Add installer `--target` option and improve growlhelper version detection
growlnotify: revamped formula using xar and pax

This makes growlnotify as native to homebrew as possible without relying
on native package installer (which is so uninstaller unfriendly).
growlnotify: simplify formula installer, prefer pkgutil instead of xar