UABE rework, Initial OSS release

"Still alive" edition

The application part of the reworked UABE is mostly written from scratch.
Key changes:
Several bundle files can be edited at once.
Files can be opened and closed without closing all files first.
The selection in the file list/tree determines the files shown for editing,
 and multiple indepentent selections can be managed using tabs.
Operations on opened files can run asynchronously (currently set to 4 threads, but no inherent limit).
The entire UABE application code is moved to shared libraries and can be referenced by plugins.
Generic asset editing is now possible within the application.
Resource editing is supported, currently only used for the generic asset editor.
Removed all mentions of neurotoxin.
UABE is now available under the Eclipse Public License v2.0.

.gitignore

@@ -0,0 +1,10 @@
+/.vs/
+/out/
+**.aps
+**.suo
+**.vcxproj.user
+/fetchcontent/*-src/
+/fetchcontent/ispc_compiler/
+/TypeTreeGenerator/.vs
+/TypeTreeGenerator/out
+/Tools/TypeTreeGenerator.pdb