Start of new ANTLR4 based parser.

Very simple tests pass.

core/SqlParser.cpp

@@ -26,7 +26,24 @@ Keyword isKeyword(const QString &symbol)
 
 	return Keyword::NotAKeyword;
 }
+/*
 
+Put tokens on a stack
+Every time something is put on the stack see if it matches a rule
+
+The stack needs to contain both tokens from the lexical analyzer as tokens for reductions done by the parser.
+
+Matching rules, as we need to match against the top of the stack we should match the rules end to start.
+Meaning if we have on the stack A B C then we need to consider rules ending with a C
+
+
+*/
+
+class StackItem {
+public:
+    int Token;
+
+};
 
 SqlParser::SqlParser(SqlLexer &lexer)
 	: lexer(lexer)