Add support with escaped FROM

If there is an escaped table in the FROM statement it throws an error.

Example:
```
var parse = require('node-sqlparser').parse;
var stringify = require('node-sqlparser').stringify;

// ERROR
var sql = 'SELECT `id` FROM `Tb`'; // escaped `Tb`
var astObj = parse(sql); // ERROR

// OK
var sqlOK = 'SELECT `id` FROM Tb';
var astObjOK = parse(sql); // OK
```

Example of the error:

```
throw peg$buildException(null, peg$maxFailExpected, peg$maxFailPos);
^
SyntaxError: Expected "$", WHITE_SPACE or [A-Za-z_] but "`" found.
```

Start at the parse entry point shown in the report and reproduce the failure with SELECT `id` FROM `Tb`, comparing it with the unescaped-table example. Trace the SQL grammar or parser rule that handles the FROM table name and add a regression test for escaped identifiers. Done means both examples parse successfully without the reported SyntaxError.

Written by the indexing model from the issue text.