Adding: criteria to all search, scheds search conf and schema validation

You can add on search config any **mongo query** you might want to do in the following way:
```
Scheds: {
...
    criteria: { between: '{ "start": { "$gte": %value% }, "end": { "$lt" : %value% } }' },
...
}
```
You can add many objects, to be used later.