Horizontal and vertical tolerance added for touch and drag gap

[sma6871]

Add padding to seekbar, then you can use isb_vertical_touch_gapand isb_horizontal_touch_gap to set bigger area for user to touch and drag thumb.

Example:

 <com.warkiz.widget.IndicatorSeekBar
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingTop="30dp"
            android:paddingBottom="30dp"
            app:isb_max="5"
            app:isb_min="1"
            app:isb_only_thumb_draggable="false"
            app:isb_vertical_touch_gap="30dp" />