[Bug 25368] Updated Dependencies, and Deprecation of Python 2.7

[MatsumiyaT]

[Bug 25368] Due to the upcoming deprecation of 'collections' in python 3.10, need to update to use 'collections.abc' for python versions >= 3.3. In order to ensure we support python versions <= 3.2, added a try/except for this to import the correct dependency. Once python versions <=3.2 are no longer supported, this can be removed. Updated SDK to import MutableSequence from collections.abc for python versions >= 3.3 and handles MutableSequence for python versions <= 3.2 using collections

[MatsumiyaT]

• Updated the dependencies for 'mutable sequence', and 'method_whitelist' to 'allowed_methods'
• Deprecation of Python v2.7; removed instances from the setup.py and the README.md
• Pulled in the MR for support include = publishedFormContainers
• Pulled in the MR for Separate DatetimeObjectValue from DateObjectValue
• Pulled in the MR for Update EnumeratedValue eq method to handle comparisons to NoneType