CLI start command to work with files

[chespinoza]

This PR addresses #79, simplify CLI code and also adds the next features:

• Create resources and start processes(pipes) using config files into a folder:
  ./device-hub-cli create -d <folder>

• Delete resources and stop existing processes using config files into a folder:
  ./device-hub-cli delete -d <folder>

• Start a process using a file:
  ./device-hub-cli start -f=../../../examples/config/http_listener_process.yaml

• Adds a new config file type for processes(pipes), e.g. process.yaml:

uri: /b
type: process
endpoint-uids:
  - stdout-endpoint
listener-uid: mqtt-helsinki-transport-service-listener
profile-uid: thingful/helsinki-bus
tags: 
  - foo:bar

In order to achieve processes management when reading config files into folders, the code implements file ordering to start processes when all required resources are already loaded and the order is reversed to stop processes at first.