title: Some issues and difficulties in PagerTabStrip
body: <p>I have implemented a scrollable tab + swipe, everything works fine.
  However I have some issues related to the current PagerTabStrip : </p>
  
  <p><strong>1.</strong> I can't make the current title Bold</p>
  
  <p><strong>2.</strong> Can't choose the default tab I want to display (e.g : the tab with position 2) when rendering the view, like the tabs in the Google Play app</p>
  
  <p><strong>3.</strong> The first and last tab have respectively a margin on the left and the right, can I set it to 0dp ?</p>
  
  <p>This is what I could do for styling the tabs :</p>
  
  <p>Java : </p>
  
  <pre><code>strip = (PagerTabStrip) findViewById(R.id.pager_tab_strip);
  strip.setTabIndicatorColorResource(R.color.light_blue);
  strip.setDrawFullUnderline(true);
  </code></pre>
  
  <p>Layout : </p>
  
  <pre><code>&lt;android.support.v4.view.PagerTabStrip
      android:id="@+id/pager_tab_strip"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_gravity="top"
      android:background="@drawable/pagertitle_border_bottom"
      android:paddingBottom="15dp"
      android:paddingTop="15dp"
      android:textColor="@color/light_blue" /&gt;
  </code></pre>
  
  <p>Can anyone help me with the 3 points ? Thank you.</p>