Fix TISTUD-4404 Log displays proxy password
  - Pass in that the password needs to be obfuscated by special ENV key-value pair
  - Modify how we do obfuscation so we replace any instances in arguments that are bookended by word boundaries (this may need to be tweaked, since we may obfuscate other areas like a filepath if the value is teh same as the password!)
  - Remove StringUtil#format entirely, use MessageFormat#format
  - Add unit tests for obfuscation of passwords
  - Fix behavior for known password patterns (URL/proxy with username and password baked in, key/value pair with value being password after an equals, password alone as an argument).