Add datavirtualization extension (#21594)

* initial

* cleanup

* Add typings ref

* fix compile

* remove unused

* add missing

* another unused

* Use newer vscodetestcover

* newer dataprotocol

* format

* cleanup ignores

* fix out path

* fix entry point

* more cleanup

* Move into src folder

* Handle service client log messages

* remove unused

extensions/datavirtualization/.vscodeignore

@@ -0,0 +1,21 @@
+# Unwanted compiled files
+out
+*.vsix
+
+# Build/Source files
+src
+test
+typings
+.gitignore
+tsconfig.json
+coverConfig.json
+tslint.json
+
+# Reference files
+**/*.ts
+**/*.map
+.gitignore
+tsconfig.json
+extension.webpack.config.js
+yarn.lock
+