Convert WPP to NET Core 3.1 (#530)

* Convert WPP to NET Core 3.1

- Copyright Update
- Hotfix Parsing
- DB2Hash update
- Update WDC3 Reader
Thanks goes to @wowdev for DBC library

* Obviously point to correct module path

* Fix SQL Database Reading

* Fix Broadcast text loading

* Rename ExecuteQuery to CreateCommand

* Travis Update

Re-Add travis-build.sh
Create travis-test.sh

* Fix BitTest for NUnit

* Fix Drag&Drop from external directory

* Fix DateTime issues

* Remove useless line in test

* Remove macOS from appveyor.yml

.NET Core 3.1 not supported yet at appveyor for macOS

* Fix output path

* Add back macOS as appveyor has .NET Core 3.1 SDK installed

Co-authored-by: Giacomo Pozzoni <giacomopoz@gmail.com>