Replace Grammar with Postgres Grammar

So much easier to add Cypher to Postgres rather than the other way

Author: JoshInnis

Makefile

@@ -42,17 +42,17 @@ OBJS = src/backend/postgraph.o \
        src/backend/optimizer/cypher_createplan.o \
        src/backend/optimizer/cypher_pathnode.o \
        src/backend/optimizer/cypher_paths.o \
-       src/backend/parser/ag_scanner.o \
+       src/backend/parser/scan.o \
        src/backend/parser/cypher_analyze.o \
        src/backend/parser/cypher_clause.o \
        src/backend/executor/cypher_delete.o \
        src/backend/parser/cypher_expr.o \
-       src/backend/parser/cypher_gram.o \
+       src/backend/parser/gram.o \
+       src/backend/parser/parser.o \
        src/backend/parser/cypher_item.o \
        src/backend/parser/cypher_keywords.o \
        src/backend/parser/cypher_parse_agg.o \
        src/backend/parser/cypher_parse_node.o \
-       src/backend/parser/cypher_parser.o \
        src/backend/parser/cypher_transform_entity.o \
        src/backend/utils/adt/queue.o \
        src/backend/utils/adt/gtype.o \
@@ -119,18 +119,19 @@ PG_CONFIG ?= pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 
-src/backend/parser/cypher_keywords.o: src/include/parser/cypher_kwlist_d.h
+src/backend/parser/keywords.o: src/include/parser/kwlist_d.h
 
-src/include/parser/cypher_kwlist_d.h: src/include/parser/cypher_kwlist.h $(GEN_KEYWORDLIST_DEPS)
-	$(GEN_KEYWORDLIST) --extern --varname CypherKeyword --output src/include/parser $<
+src/include/parser/kwlist_d.h: src/include/parser/kwlist.h $(GEN_KEYWORDLIST_DEPS)
+	$(GEN_KEYWORDLIST) --extern --varname PG_KEYWORD --output src/include/parser $<
 
-src/include/parser/cypher_gram_def.h: src/backend/parser/cypher_gram.c
 
-src/backend/parser/cypher_gram.c: BISONFLAGS += --defines=src/include/parser/cypher_gram_def.h
+src/include/parser/gram_def.h: src/backend/parser/gram.c
 
-src/backend/parser/cypher_parser.o: src/backend/parser/cypher_gram.c
-src/backend/parser/cypher_keywords.o: src/backend/parser/cypher_gram.c
+src/backend/parser/gram.c: BISONFLAGS += --defines=src/include/parser/gram_def.h
 
-src/backend/parser/ag_scanner.c: FLEX_NO_BACKUP=yes
+src/backend/parser/parser.o: src/backend/parser/gram.c
+src/backend/parser/keywords.o: src/backend/parser/gram.c
+
+src/backend/parser/scan.c: FLEX_NO_BACKUP=yes
 
 installcheck: export LC_COLLATE=C