Project can't be created without Z option

[snjeza]

Reproduction Steps:

• set the option
  che.docker.volumes_projects_options=
• try to create a project

Expected behavior:

The project is created.

Observed behavior:

You will encounter a 500 internal error

Che version: 5.0.0-M8-SNAPSHOT, rev 13000b0
OS and version: Fedora 24
Docker version: 1.12.3
Che install: Docker container

Additional information:

• Problem started happening recently, didn't happen in an older version of Che: [No]
• Problem can be reliably reproduced, doesn't happen randomly: [Yes]

[ghost]

@snjeza what's your expected behavior? Z suffix has been added to make it possible to do mounts on Fedora and RHEL. And yes, without it you cannot do mounts even using just pure Docker. Am I wrong?