GitLab support, content searching, performance enhancements, docker support

[codeEmitter]

• Support for GitLab users and groups
• Support for multiple modes of execution including content search
  • Mode 1 - Default mode to match on file signatures.
  • Mode 2 - Match on file signatures then content signatures to constitute a result.
  • Mode 3 - Match on content signatures only without file signature matches.
• Support for in-memory repository clones, which can result in significantly faster analysis times depending on your hardware.
• File signatures for Google Cloud Platform credentials
• Content signatures similar to trufflehog.
• Docker support

Closes #193