Add file connector helpers

[codeliner]

Add some file connector helpers:

• [ ] Download file
  • always into inbox
• [ ] Upload file
  • Configure location and filename pattern to pick up files to upload
  • Configure service endpoint / Ginger Node Name
  • Configure protocol http(s) / (s)ftp
• [ ] Rename file
  • Configure read location / filename pattern and write location filename template
• [ ] Zip files
  • Configure read location / filename pattern and write location filename template
• [ ] Clean up location
  • Configure location to clean up and filename pattern
• [ ] Add standard file upload endpoint
  • always into inbox
  • trigger process if configured filename pattern matches

[codeliner]

Depends on #25