Actors in Makefile: parameterize ACTOR_DIRECTORY and escape $ in echo messages

Change the string ~/public/PYTHON_ACTORS to a variable (same value), in order that it can be overwritten from the make command.[1] Also escape some $ symbols in echo messages.

[1] As previouesly discussed in !18 (merged)

src-f90/Makefile

@@ -17,6 +17,9 @@ PROG_TEST_CHEASE_Q = test_chease_q
 PROG_TEST_CHEASE_CI_SHORT = test_chease_ci_short
 PROG_TEST_CHEASE_IMAS_CI_SHORT = test_chease_imas_ci_short
 
+# Set default Actor directory path
+PYTHON_ACTOR_DIRECTORY ?= ~/public/PYTHON_ACTORS
+
 # Define variable CHEASE_F90 which will then be used to defined the compilation flags automatically
 
 ## these tests worked:
@@ -319,20 +322,20 @@ ifneq (,$(findstring csh,$(SHELL)))
 else
 	. ../build_iwrap.sh
 endif
-	iwrap -f ../iwrap/chease.yaml -i ~/public/PYTHON_ACTORS
-	export PYTHONPATH=/home/ITER/sautero/public/PYTHON_ACTORS:$PYTHONPATH
-	@echo "can test with: mkdir -p /tmp/$USER; cd /tmp/$USER; python $PWD/python/run_chease_iwrap.py > /tmp/$USER/o.run_chease_iwrap.py"
+	iwrap -f ../iwrap/chease.yaml -i $(PYTHON_ACTOR_DIRECTORY)
+	@echo "can set python path with: export PYTHONPATH=$(PYTHON_ACTOR_DIRECTORY)/chease:$$PYTHONPATH"
+	@echo "can test with: mkdir -p /tmp/$$USER; cd /tmp/$$USER; python $$PWD/python/run_chease_iwrap.py > /tmp/$$USER/o.run_chease_iwrap.py"
 
 $(PROG_ACTOR_FC2K):
 ifneq (,$(findstring csh,$(SHELL)))
-	cd ..; source build_fc2k.csh; fc2k fc2k_imas/chease.xml -nokepler -pyworkspace ~/public/PYTHON_ACTORS
+	cd ..; source build_fc2k.csh; fc2k fc2k_imas/chease.xml -nokepler -pyworkspace $(PYTHON_ACTOR_DIRECTORY)
 else
-	cd ..; . build_fc2k.sh; fc2k fc2k_imas/chease.xml -nokepler -pyworkspace ~/public/PYTHON_ACTORS
+	cd ..; . build_fc2k.sh; fc2k fc2k_imas/chease.xml -nokepler -pyworkspace $(PYTHON_ACTOR_DIRECTORY)
 endif
 
 	@echo " "
 	@echo "Now can test with: "
-	@echo 'export PYTHONPATH=/home/ITER/sautero/public/PYTHON_ACTORS/chease:$$PYTHONPATH'
+	@echo 'export PYTHONPATH=$(PYTHON_ACTOR_DIRECTORY):$$PYTHONPATH'
 	echo "mkdir -p /tmp/$(USER); cd /tmp/$(USER); python $(shell cd ..;pwd)/python/run_chease_fc2k.py > /tmp/$(USER)/o.run_chease_fc2k.py"
 
 $(FUTILS)/lib$(futils).a :