10.9 CLI tools has same name as 10.10, simplifies xcode-cli-tools.sh

- as of 6.0, CLI tools for 10.9 are now named the same as 10.10 tools
- 10.10 tools (at this very moment) actually get listed four times, so add a 'head -n 1' to just take the first result.
  - this is probably temporary until Apple consolidates their updates in their sucatalog
Cleanup script whitespace