Not handling strings with numbers correctly

If you try to search for string like: AZ12878
using regex parameter for example: AZ1
then you'll get no results, because of incorrect processing of string.

I think the problem is on line 120 and solution is:
```
@@ -117,7 +117,7 @@ module.exports = exports = function apiQueryPlugin (schema) {
           } else {
             addSearchParam({$in: options});
           }
-        } else if (val.match(/([0-9]+)/)) {
+        } else if (val.match(/^[0-9]+$/)) {
           if (operator === "gt" ||
               operator === "gte" ||
               operator === "lt" ||

```
I've prepared updated tests and fixtures ready to merge.