Remove iterator config

Removed SentenceIterator from validator configuration.

Current configuration

    <component name="Validator">
       <component name="SentenceIterator">
           <component name="SentenceLength"/>
           <component name="SpaceAfterPeriod" />
       </component>
    </component>

New configuration.

    <component name="Validator">
        <component name="SentenceLength"/>
        <component name="SpaceAfterPeriod" />
    </component>

Ref #166.