refact: remove almost all files

This is a prepare commit for the following refactor of
dde-application-manager.

I remove almost all files in this git repository.

We will start the refactor in later commits.

Signed-off-by: black-desk <me@black-desk.cn>

.gitignore

@@ -1,6 +0,0 @@
-CMakeLists.txt.user
-build/
-
-# translations files
-*.qm
-.vscode/