list extensions functionality

This adds functionality to list all extensions installed on a tenant. While you can also get this from the File Repository in Cumulocity, having it in the script is more convenient especially if lots of non-extension files exist in the tenant.

Implementation uses the standard mechanisms of the SDK to provide an additional command "list extensions" (note the plural)
ignoreVersion is not implemented as the list functionality should not be version specific
As no paging is implemented, this will work for up to 2000 extensions installed on a tenant.
Output is just the list of extensions with each extension on a new line to allow for easy inclusion in other scripts

SoftwareAG / apama-analytics-builder-block-sdk

list extensions functionality #1