v0.3: Faster and stronger

- Reduce executable size with compiler flags
- Read log files and authorized keys concurrently
- Display algorithm security
- Ignore comment lines in authorized_keys (issue #2)
- Rename CSV columns:
    name -> comment
    insecure -> secure
    lastuse -> last_use
    lastip -> last_ip
    fingerprint -> fingerprint_md5
- Rename flag:
    fingerprint -> fingerprint-md5
- Use Go 1.9.4

v0.2: Release

- Add flag -csv
- Add flag -fingerprint
- Show last used ip in aligned table
- Parse key type and length from public key
- Add more unit tests
- Fix log file parsing (accept all key types)
- Use Go 1.9 for releases

v0.1

Display key table with last use and usage count