Fix $namespace and $metric variables

$namespace
In the previous version, the list of namespaces was hardcoded for the $namespace variable.
Today the list of namespaces depends on region and compartment.

$metric
In the previous version, the $metric variable depends on the home region, $compartment and hardcoded $namespace.
Today $metric depends on $region, $compartment and $namespace.

V1.0.3

Fix issue:
Metric name rule creation updated

v1.0.2

• Shows subcompartments and removes inactive compartments from that list
• Changes Metric names when rendering on the screen, uses a human readable name for the resource if one is present
• Shortens ocids to first three and last six characters to save screen real estate

v1.0.1

Pulls in regions dynamically
Adds more documentation