Update default library state to material design

New look and feel of the library that follows material design
guidelines. This update of the library introduce:

- Change the default parameters of the tabs layout to make
it look like more material.

- The indicator is center by default while swiping tabs.

- The alpha value of the titles change depending the
selected position.

- Ability to change the divider width (No material change).

- Ability to pass customTabs implementing the interface
'CustomTabProvider' in your adapter (dev can use ripple
effect on the tabs).In case the customTab have
a view with id '@+id/tab_title', it will be use to place
the title and alpha will act as usual. If this interface is
not implemented then, the default Tab layout will be use (TextView).
Increased compatibility to API > 9
Update README.md
Cleanup code according to comments of jpardogo
Ability to set padding to tabs but keep the offset in the middle (Like Newsstand)
Update gradle plugin to 0.14
Merge branch 'master' of https://github.com/pietervdheijden/PagerSlidingTabStrip into pietervdheijden-master
import android.annotation.SuppressLint
Merge branch 'pietervdheijden-master'
Merge branch 'master' into paddingTabs
Newsstand tabs like allowed via attr pstsPaddingMiddle

The tabs can start in the middle of the view width
and keep the selected position in the middle. The
unselected tabs keep visible while swiping.

- app:pstsPaddingMiddle accept a boolean value
Make sure the padding is equal in eahc side (if set)
Padding and offset calculation polish

- Make sure the padding is equal in each side (if set)
- Calculation of the offset with lines diff only if neccesary
Update README
Update README
Merge branch 'paddingTabs' branch for the option to have tabs like Newsstand google app
Update README
Update README
Fix ViewPager.setCurrentItem() doesn't sync to tab

Fix ViewPager.setCurrentItem() doesn't sync to tab if page is not visible when called
Check if tabCount > 0 before attempting tabsContainer.getChildAt(position) when scrolling to child.

Ref : https://github.com/astuetz/PagerSlidingTabStrip/pull/89