Make the settings objects respond to direct click

Before the modification - in order to change the values in the settings -
the user would have to click the "pencil" icon at the right. This is
counter intuitive as all of the settings activities respond to direct
clicks on the object.

- Implement onClickListeners to RelativeLayouts in which the settings are
  contained.
Show visual response to Settings object onClick

- Implement a selector and a drawable that will be called in case the
  relative layout that holds the preference object gets clicked.