add key-tau into one runnable thing

[wadoon]

Intended Change

Adds key-tau in a simple and usable form. Just start using the Jar file or keyext.web:run.

In the background, Netty is started to serve the HTML/JS part and provide the WS endpoint (http://localhost:8080, and ws://localhost/ws/jsonrpc).

Best experience with google-chrome and --app=http://localhost.

Plan

• Discussion about key-tau future
• Context menu problems
• A lot of exceptions popping up

[github-code-quality]

Code Coverage Overview

Languages: Java

Java / code-coverage/jacoco

The overall coverage in commit 9e2f95f in the weigl/tau branch is 14%. The coverage in commit 836e23e in the main branch is 15%.

Show a code coverage summary of the most impacted files.

File	main 836e23e	weigl/tau 9e2f95f	+/-
org/key_project...etEndpoint.java	0%	0%	0%
org/key_project...ebui/WebUi.java	0%	0%	0%