Refactor & fix unsafe pg and fb identifiers

[mkgrgis]

Full test:

CREATE TABLE "AB" ("AB" int, "Ab" INT, "aB" INT, "ab" INT, "c" boolean);
CREATE TABLE "aB" ("AB" int, "Ab" INT, "aB" INT, "ab" INT, "c" boolean);
CREATE TABLE "Ab" ("AB" int, "Ab" INT, "aB" INT, "ab" INT, "c" boolean);
CREATE TABLE "ab" ("AB" int, "Ab" INT, "aB" INT, "ab" INT, "c" boolean);
INSERT INTO "AB" ("AB","Ab","aB","ab","c") VALUES
     (1,2,3,4,false);
INSERT INTO "AB" ("AB","Ab","aB","ab","c") VALUES
     (5,6,7,8,true);
INSERT INTO "AB" ("AB","Ab","aB","ab","c") VALUES
     (9,10,11,12,NULL);
INSERT INTO "aB" SELECT * FROM "AB";
INSERT INTO "Ab" SELECT * FROM "AB";
INSERT INTO "ab" SELECT * FROM "AB";

INSERT INTO AB ("AB","Ab","aB","ab","c") VALUES
     (1,1,1,1,false);
INSERT INTO "Ab" ("AB","Ab","aB","ab","c") VALUES
     (2,2,2,2,false);
INSERT INTO "aB" ("AB","Ab","aB","ab","c") VALUES
     (3,3,3,3,false);
INSERT INTO "ab" ("AB","Ab","aB","ab","c") VALUES
     (4,4,4,4,false);

DROP TABLE "ΓΔ";
DROP TABLE "γΔ";
DROP TABLE "Γδ";
DROP TABLE "γδ";

CREATE TABLE "ΓΔ" ("ΓΔ" int, "Γδ" INT, "γΔ" INT, "γδ" INT, "c" boolean); CREATE TABLE "γΔ" ("ΓΔ" int, "Γδ" INT, "γΔ" INT, "γδ" INT, "c" boolean); CREATE TABLE "Γδ" ("ΓΔ" int, "Γδ" INT, "γΔ" INT, "γδ" INT, "c" boolean); CREATE TABLE "γδ" ("ΓΔ" int, "Γδ" INT, "γΔ" INT, "γδ" INT, "c" boolean); INSERT INTO "ΓΔ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (1,2,3,4,false);
INSERT INTO "ΓΔ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (5,6,7,8,true);
INSERT INTO "ΓΔ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (9,10,11,12,NULL);
INSERT INTO "γΔ" SELECT * FROM "ΓΔ";
INSERT INTO "Γδ" SELECT * FROM "ΓΔ";
INSERT INTO "γδ" SELECT * FROM "ΓΔ";

INSERT INTO "ΓΔ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (1,1,1,1,false);
INSERT INTO "Γδ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (2,2,2,2,false);
INSERT INTO "γΔ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (3,3,3,3,false);
INSERT INTO "γδ" ("ΓΔ","Γδ","γΔ","γδ","c") VALUES
     (4,4,4,4,false);