Search operator position is better at param key

Usually users do not input operators like `(ge)2018-04-16`
It make view code little hacky like change values before send

I think operators should be in query keys, not values like below
```
Now
<input name="foo" value="(ge)2018-04-16">
My opinion
<input name="(ge)foo" value="2018-04-16">
```