Update .gitignore.
Lots of updates

1. Look up rpm files in specified directory with glob.
2. Extract Oracle version number via re.findall()
3. Use context managers for file operations.
4. General PEP8 issues.
Rename system_setup.py -> install_oracle_instantclient.py
Ignore Vagrantfile
Exclude rpm files from inclusion in the repo.
Remove rpm files.

This need to be downloaded by the end-user per Oracle's license agreement.