VM: merge of the free_list and free_list_allocator classes

Seem simpler to have all the free list stuff in one class rather than
split it over two classes.

GNUmakefile

@@ -43,7 +43,6 @@ ifdef CONFIG
 		vm/entry_points.o \
 		vm/errors.o \
 		vm/factor.o \
-		vm/free_list.o \
 		vm/full_collector.o \
 		vm/gc.o \
 		vm/image.o \

Nmakefile

@@ -67,7 +67,6 @@ DLL_OBJS = $(PLAF_DLL_OBJS) \
 	vm\entry_points.obj \
 	vm\errors.obj \
 	vm\factor.obj \
-	vm\free_list.obj \
 	vm\full_collector.obj \
 	vm\gc.obj \
 	vm\image.obj \

vm/code_blocks.cpp

@@ -301,7 +301,7 @@ code_block* factor_vm::allot_code_block(cell size, code_block_type type) {
     if (block == NULL) {
       std::cout << "Code heap used: " << code->allocator->occupied_space()
                 << "\n";
-      std::cout << "Code heap free: " << code->allocator->free_space() << "\n";
+      std::cout << "Code heap free: " << code->allocator->free_space << "\n";
       fatal_error("Out of memory in add-compiled-block", 0);
     }
   }

vm/data_heap.cpp

@@ -93,7 +93,7 @@ bool data_heap::high_fragmentation_p() {
 }
 
 bool data_heap::low_memory_p() {
-  return tenured->free_space() <= high_water_mark();
+  return tenured->free_space <= high_water_mark();
 }
 
 void data_heap::mark_all_cards() {
@@ -123,9 +123,9 @@ data_heap_room factor_vm::data_room() {
   room.aging_free = data->aging->free_space();
   room.tenured_size = data->tenured->size;
   room.tenured_occupied = data->tenured->occupied_space();
-  room.tenured_total_free = data->tenured->free_space();
+  room.tenured_total_free = data->tenured->free_space;
   room.tenured_contiguous_free = data->tenured->largest_free_block();
-  room.tenured_free_block_count = data->tenured->free_block_count();
+  room.tenured_free_block_count = data->tenured->free_block_count;
   room.cards = data->cards_end - data->cards;
   room.decks = data->decks_end - data->decks;
   room.mark_stack = mark_stack.capacity() * sizeof(cell);