Add ElementPagerActivity with viewPager
Create ElementFragment class
Create method toFragment in Element.java
Implement onElementClickListener in ElementPagerActivity
Add ElementPagerActivity to Manifest file
Solve some errors
Make a button for testing the new activity
implement CalculateListener.onClickCalculateListener
Add padding to ElementFragment

Solve code error
Solve error not showing calculateFragment
Don't show list menu item when current page is list
Change titles in action bar
Change some layout
Manage back stack
Add some colors
Add some resources to repository
Complete Dutch translation
Prepare for release v2.0