docker.userguide: Fix manual grafana and influxdb run commands

docker.userguide: Fix manual grafana and influxdb run commands

Previously ports were exported for grafana and influxdb but
no network was mapped - no connection was possible between
both containers (only connection from host to container
was possible).
Now container network is mapped to host - the same approach
is used by ansible automatic installation for collectd,
influxdb and grafana containers.

Change-Id: I81af33d028bb8bc55590324694af93993f0f1d8c
Signed-off-by: Radoslaw Jablonski <radoslawx.jablonski@intel.com>