Support of additional ESCAPE option for Oracle and MSSQL support to prevent empty results

[Ragnaroe]

First of all I'm new to github and not that experienced with the processes here.
The query builder is a great tool and I would like to address issues this has with the wildcard characters _ and % when the queries formed by the query builder are submitted to an Oracle or MSSQL Server DBMS.
So while the like operators, e.g. "contains" will have the wildcards escaped to _ and % but without the additional specification of the ESCAPE character it will not work in Oracle and MSSQL in my environment.
E.g.: name LIKE '%TEST_%' would have to be converted as follows: name LIKE '%TEST_%' ESCAPE '' to find "TEST_TEST"
This would be also compatible with PostGreSQL.

For building the sql, I would add the following lines at the line 5968 in query-buider.standalone.js:

if (rule.operator == 'begins_with' || rule.operator == 'not_begins_with' || rule.operator == 'contains' || rule.operator == 'not_contains' || rule.operator == 'ends_with' || rule.operator == 'not_ends_with') {
                                value += " ESCAPE '\\'"
}

However, the adjustment in the sqlparser is missing to be able to interpret this ESCAPE '' statement again.
Is there any chance that this will be addressed by you?

[sKUZZLEbut1808]

Got the same issue.
Any update on that?
Would be really helpful