Python-opsramp

* Updated examples
* Unused [eventlet](https://pypi.org/project/eventlet/) dependency removed
* Bug fix for attach & detach of Management Profiles
* Add support for retries in response to OpsRamp rate limiting (HTTP 429 responses)

This adds support for OpsRamp "resources" and includes two samples, one of which (resources_list) can be used to dump the set of resources on a tenant in YAML format.

A Permission Set is conceptually like a bitmask of individual RBAC permissions and they are used in the construction of Roles. Currently they can only be read through the OpsRamp API, not created or modified. It's still important to be able to read them because you need to specify a permission set ID when you're creating a Role and the ID values are different on every system so you have to iterate over them to find the ID you want.

Important bugfix to handling of text responses on Python 3.

The exception type that is returned for JSON parse errors was incorrect
in our code because the requests module uses the simplejson module
for parsing and we assumed the regular json module.

This is an initial baseline release for the python-opsramp project. It was partly prompted by mislabelling of the previous release as 0.16 instead of 0.0.16 but in reality we were overdue to declare a proper 1.0 release anyway.

Most recent change is to use the same "requests" session for all http(s) calls from a single binding object. This is a more efficient use of resources in the requests package and makes this entire module more amenable to testing with "betamax" which is a medium-term goal for the project.

Also in this release: update and delete for RBA categories.

OpsRamp sometimes returns multi-page responses and previously only the first page would be returned by this library. This release attempts to pull all pages into a single returned dict. That does mean the caller could run out of memory if the response is enormous, however we do need to do something because OpsRamp's page size is small.