* PLT-3193 Add channel notification preferences for push and email notifications
* unit tests, model validation and localization
* Feedback review
* Adding back allowFromCache check
* Setting push and email to use default settings
* Move props as constants
* address feedback
* Implement POST /channels/members/{user_id}/view endpoint for APIv4
* Implement PUT /channels/{channel_id}/members/{user_id}/roles endpoint for APIv4
* Implement DELETE /channels/{channel_id}/members/{user_id} endpoint for APIv4
* added get session and revoke session endpoints, unittests and drivers
* removed BasicUser2 and added teardown
* added badrequest unit test case for sessions
* added session loop to check if user id and session user id matches
* fixed indentation issues for user_test
* match indentation from spaces to tabs
* implement get channels endpoints and updated drivers and unittests
* removed channel deletion on tear down, removed manage permission on get channels endpoints, and updated utils to add constant channel length
* added constants for user, team and channel length, updated context to use the model functions
* make sure team name length should be less than the minimum length and revert underscore to team name validity
* changed post test condition from notfound to unauthorized
* Implement POST /posts endpoint for APIv4
* Implement GET /channels/{channel_id}/posts endpoint for APIv4
* Implement GET /posts/{post_id} endpoint for APIv4
* Implement GET /posts/{post_id}/thread endpoint for APIv4
* Skip team get if it's a DM channel in handlePostEvents
* Adding go vet to the api package
* Adding go vet to app package
* Adding go vet to manualtesting package
* Adding go vet to the model package
* Adding go vet to the store dir
* Adding go vet to utils package
* Adding missing dirs with go files
* Fixing up makefile
* Fixing up makefile
* Removing root dir
* added get user by username endpoint
* added get user by username unit test and driver
* changed username length to 22 characters max
* changed Params to UserName to Username
* reorganized get user by username and get user by email formatting in model/client4
* Implement GET /channels/{channel_id}/members
* Implement GET /channels/{channel_id}/members/{user_id} endpoint for APIv4
* Implement /users/{user_id}/teams/{team_id}/channels/members endpoint for APIv4
* Fix unit test
* added get user by email endpoint for APIv4
* added get user by email endpoint unit test and driver
* removed the appended return of user ids on logout
* Added RequireEmail to validate user email. Also updated the get user by email endpoint and unit test
