Allow users to configure the TOTP Algorithm and Digits. This should be used with caution as many TOTP applications do not support it. Some will also fail to notify the user that there is an issue. i.e. if the algorithm in the QR code is sha512, they continue to generate one time passwords with sha1. In addition this drastically refactors TOTP in general to be more user friendly by not forcing them to register a new device if the administrator changes the period (or algorithm).
Fixes#1226.
* added regulation validator
* made regulations find_time and ban_time values duration notation strings
* added DefaultRegulationConfiguration for the validator
* made session expiration and inactivity values duration notation strings
* TOTP period does not need to be converted because adjustment should be discouraged
* moved TOTP defaults to DefaultTOTPConfiguration and removed the consts
* arranged the root config validator in configuration file order
* adjusted tests for the changes
* moved duration notation docs to root of configuration
* added references to duration notation where applicable
* project wide gofmt and goimports:
* run gofmt
* run goimports -local github.com/authelia/authelia -w on all files
* Make jwt_secret error uniform and add tests
* now at 100% coverage for internal/configuration/validator/configuration.go
* Add period TOPT config key to define the time in seconds each OTP is rotated
* Add skew TOTP config to define how many keys either side of the current one should be considered valid
* Add tests and set minimum values
* Update config template
* Use unix epoch for position calculation and Fix QR gen
* This resolves the timer resetting improperly at the 0 seconds mark and allows for periods longer than 1 minute
* Generate QR based on period
* Fix OTP timer graphic
James Elliott
Amir Zarrinkafsh
Clement Michaud