Clean up instruction loop, more cleaning up

"clean" Makefile target
Rearrange DEBUG constants so least bits trigger output with most impact
New "implemented" bool SoftSwitch
Add page2 handling to textport (untested)
Separate out "region" encapsulating address start and end for convenience
Factor out "set_flags()" for most common "flag_change()" sequences
Move comment with instruction opcode onto case for compactness
Remove old disassembly in favor of open source disassembly

Makefile

@@ -1,6 +1,11 @@
-CXXFLAGS=-O -Wall --std=c++11
+CXXFLAGS        = -g -O -Wall --std=c++11
+
+OBJECTS         = apple2e.o keyboard.o dis6502.o
 
 all: apple2e
 
-apple2e: apple2e.o keyboard.o dis6502.o
-	$(CXX) $(LDFLAGS) $^ -o $@ $(LDLIBS)
+apple2e: $(OBJECTS)
+	$(CXX) $(CXXFLAGS) $(LDFLAGS) $^ -o $@ $(LDLIBS)
+
+clean:
+	rm $(OBJECTS)