add a clangd and qtcreator make targets

Add a clangd make target:
$ make clangd
This installs a .clangd file with configuration (includes/macros/compiler flags)
for the clandg language server.

Add a qtcreator make target:
$ make qtcreator
This installs a .qtcreator directory with QTCreator IDE project files.
In the QTCreator you can open a project by selecting the .qtcreator/ezc.creator
file.

You can use 'make qtcreator' again to refresh .qtcreator/ezc.files,
the rest of the project files will not be modified.

Makefile

@@ -20,6 +20,13 @@ depend: FORCE
 	$(MAKE) -C src depend
 
 
+clangd: FORCE
+	@.templates/install_clangd.sh
+
+
+qtcreator: clangd
+	@.templates/install_qtcreator.sh
+
 
 FORCE: