Refactoring code.

- Moving task logic into existing ServerManager class.
Refactoring code.

- Moving task logic into new ServerInstaller class.
- Converting procs to new DebianInstaller and RedhatInstaller classes.
Refactoring code.

- Moving task logic into new NodeInstaller and NodeManager classes.
Refactoring code.

- Moving task logic into new LogManager class.
Refactoring code.

- Moving task logic into new ForgingManager class.
Refactoring code.

- Moving task logic into existing KeyManager class.
Calling block(s) regardless of success.
Removing unnecessary dependency check.
Removing unnecessary dependency check.
Removing unnecessary object checking.
Privatising methods.