Dropbox

* Fixed Sphinx documentation entires.
* Added missing namespace: seen_state.
* Removed deleted namespace: properties.

file_properties namespace:
- updated comments

files namespace:
- new FileId alias
- new SymlinkInfo struct on FileMetadata
- added select_admin_mode attribute to relevant routes
- added too_many_write_operations error type to WriteError
- New CreateFolderBatch endpoint and related datatypes
- Added parent_rev attribute to DeleteArg
- New Thumbnail sizes
- New ThumbnailMode object
- New SyncSettings objects

sharing namespace:
- added select_admin_mode attribute to relevant routes
- add seen_State.PlatformType to UserFileMembershipInfo
- new set_access_inheritance for FolderAction
- Updated docs
- additional user info added to UserInfo struct
- new AccessInheritance union
- new set_access_inheritance route

team namespace:
- updated docstrings
- new HasTeamSelectiveSync object
- new selective sync settings included in various return objects and error types
- new update_sync_settings route

team_log namespace:
- updated event types

team_policies namespace:
- new ShowcaseEnabledPolicy object
- new ShowcaseDownloadPolicy object
- new ShowcaseExternalSharingPolicy object

users namespace:
- updated routes with select_admin_mode attribute.

Fix regression in `Dropbox.as_admin()` and `Dropbox.as_user()`

Added `with_path_root` helper utility to Dropbox base class to facility stetting `Dropbox-API-Path-Root` header. See https://www.dropbox.com/developers/reference/namespace-guide#pathrootmodes for more information about the path root header.

team_common namespace:
- Added new MemberSpaceLimitType union

team namespace:
- add additional error types to MembersRemoveError union
- updated docstring

users namespace:
- additional member space limit fields in TeamSpaceAllocation struct

team_log namespace:
- lots of updates to struct names and descriptions (note these routes and structs are still in preview and subject to further changes)

Release Notes:

- files namespace
- Add download_zip endpoint
- Add properties_error to UploadError
- team_log namespace
- Add more event types