* Feature/hostingstartup (#80)

* Update TargetFrameworkVersion

* Update appveyor.yml

* Feature/hostingstartup (#81)

* Update TargetFrameworkVersion

* Update appveyor.yml

* Update appveyor.yml

* Update version.props

* Add ISkyWalkingClient interface

* Refactor

* Fix ProjectReference

* Fix PackageReference

* Fix  System.Threading.ThreadPool

* Refactor IComponents

* Update appveyor.yml

* Update version.cake

* Fix namespace

* Remove SkyWalking.Dictionarys

* Refactor

* Refactor ServiceDiscoveryService

* Refactor

* Refactor

* Add TraceSegmentTransportService

* Blocking dispatcher strategy

* Add gRPC Transport

* Add InstrumentationHostedService

* Refactor skywalking logger

* Agent function test.

* Add debug log

* Fix trace segment queue

* Refactor AsyncQueueTraceDispatcher

* re-naming

* Rename gRPCClient

* Refactor SkyWalking.Utilities

* Trace data sent to collector

* Add SkyWalkingHostingStartup

* Fix peer transform

* Refactor ContextCarrier

* Refactor SkyWalking.AspNet

* Update appveyor.yml

* Fix CI

* Cleanup tests that are no longer applicable