Added JWT functionality, fixed bugs

In order to follow semver, I need to bump this release to 1.0.0 due to backwards incompatibility. This is still not a final product.

Added IIdentitySerializer and fixed sign out issues

v0.2.0

Fixed sign out issues and added IIdentitySerializer::deserialize()

MVP Release + fixes and documentation

v0.1.1

JWTUserStorage::getLogoutReason() now returns value of the property i…

MVP Release

The JWT User Storage should now work in the primary use-case, but can be unstable. Tests and bugfixes incoming!