Merge pull request #1 from thinktecture/master

sync from main thinktecture:master
Resolves runtime error due to Jwt not 3.0.0

At runtime the CodeFlowClient app was failing to deserialize the JWT due
to the Thinktecture.IdentityModel.Oidc.dll referencing
System.IdentityModel.Tokens.Jwt nuget 3.0.0 but the CodeFlowClient was
using 1.0.0
Merge pull request #545 from eldiosyeldiablo/master

Resolves runtime error due to Jwt not 3.0.0