QueryBuilder should throw exception or issue warning when quering on unindexed property

[musketyr]

Given simple script

import groovyx.gaelyk.datastore.*
import groovy.transform.*

@Entity @Canonical @CompileStatic class Comment {
    String title
    String body
}

new Comment(title: 'Title', body: 'Body').save()

assert Comment.count{ where title == 'Title' } == 0

We might expect result 1 instead of 0. Result is zero because the value is unindexed.