Added new feature that ssh with ec2 name tag, and some fixed a bit.

- added -n option that ssh with ec2 Name tag.
- fixed -d option indent.
- fixed function name.
- modified gitignore.
Merge branch 'develop' into feature/ssh_with_name
Merge pull request #2 from reiki4040/feature/ssh_with_name

Feature/ssh with name
Added default ssh host type with RNZOO_SSH_HOST_TYPE env variable.

added -P option that ssh with Public IP.
removed debug echo...
version 0.2.1 some improve and bug fix.

Improve
  - Added RNZOO_SSH_HOST_TYPE that environment variable for default ssh host type.
  - Added -P option that ssh with Public IP.
  - Added -n option that ssh with ec2 name tag

Bug fix
  - some bugs fixed.