Added minver

Marking old async methods obsolete in preparation for proper async re…

…factoring

Up to 106.6.10

Updated the comment as per restsharp#1271

Fixes restsharp#1258

Adding dotnet restore

Merge pull request restsharp#1121 from mscharrig/develop

Fixes restsharp#1104

Added a request configurator

Fixing restsharp#1061