Refactor and cleanup the RegExp parser

JerryScript-DCO-1.0-Signed-off-by: Szilard Ledan szledan.u-szeged@partner.samsung.com

tests/jerry/regexp-simple-atom-and-iterations.js

@@ -53,3 +53,6 @@ assert (r.exec ("aaaaaaa") == "aaaaaa");
 
 r = new RegExp (".*");
 assert (r.exec ("abcdefghijkl") == "abcdefghijkl");
+
+r = /\n/;
+assert (r.exec ("\n") == "\n");