CSC-6644 Add a stable channel support for batch requests

CSC-6132 Sync Status Indicator for Calendar Events

CSC-6369 Outlook Update/Delete contact sync doesn't work

CSC-6138 Migrate auth to new libraries

CSC-6074 Add MasterCategoriesService

CSC-6035 Fix AttributeError in Office365ClientError

CSC-5423 Add beta service

CSC-5527 Prevent attempt to execute empty batch request

CSC-5446 two_way_contact_sync - InvalidJSONError

CSC-5399 Utilise requests library (#31)

* CSC-5399 Change SSL config

* CSC-5399 Change TLS to 1.2

* CSC-5403 Add retries for SSLEOFError

* CSC-5403 Add max_entries param to contacts delta_list

* CSC-5399 Two way sync fails with SSLEOFError

* CSC-5439 The Send later functionality doesn't work in Outlook - Attempts to send the delayed email have failed

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Co-authored-by: Andrew Matsukov <[email protected]>