This fixes the docker build, that was failing while installing N2VC due
to a new version of websockets that was released.

We specifically install the latest 4.x release of websockets, known to
be compatible with libjuju, in conjunction with a patch to N2VC that
specifies the version requirement.

Installing the specific version is necessary because websockets is being
installed as a dependency to another python library that is installing
5.0, but installing 4.1 satisfies its requirements.

Change-Id: I390b2c3663f21b29e8527783d153127ca405ea8e
Signed-off-by: Adam Israel <adam.israel@canonical.com>

Change-Id: I0d1250a1666b7ba92f3a95f6b196f54ea8f9cd75
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>

Change-Id: I564b15603af86a7e0482347c204ce711d36c25fc
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>

Change-Id: Ibb3d2cb9257c11f00139e7a5448aed7a1ccd2830
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>

Allow logging at file

Change-Id: I1e8a80249e40344a15017a1e6eca0f110534d461
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>

Change-Id: I13835e7db4febfc4f625297936ab343e02d99402
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>