82ba182: Make docker engine port configurable

Introduced -engine-port flag in create subcommand
Extended drivers interface with a GetPort() method
Updated all drivers with the new interface
Updated provisioning to use GetPort() rather than parse GetURL() for the port
Made driver options for setting the engine port emit a useful error message
Fixes #3361

Signed-off-by: Wouter Dullaert <[email protected]>
(cherry picked from commit edad5f7c23854603de7e650b8eae10c52168e961)

fc8bded

Made docker engine port configurable using -engine-port flag in creat…

a6a5995: Add mount command for mounting machine directories

This comes in handy, when wanting to use volumes with drivers that
don't support folder sharing (such as KVM, as opposed to VirtualBox)

You will need FUSE and SSHFS installed, in order to use this feature.
The machine will also need a "sftp" binary, but most of them have it.

Signed-off-by: Anders F Björklund <[email protected]>
(cherry picked from commit 30de5bb722ec23a71fc9f7d9a3f1f9236129970e)

0cbe7eb

Fall back to default, if GetPort is not available