Reset the state of matrix object using a proper reset method.

The Matrix method 'set(null)', with null parameter, works fine on emulators and real
devices, but doesn't play well in unit tests with Robolectric, which
throw an Exception after checking for null params.

Since a proper method for reseting the state of Matrixes are available,
should not be an issue using it.
Create about_libraries_def.xml

Allows AboutLibraries (https://github.com/mikepenz/AboutLibraries) to autodetect the usage of this library and show it on a dialog.
Update about_libraries_def.xml

Same Indent (tab) at all rows, author website changed to github.
Update about_libraries_def.xml

Missing > added
Merge pull request #56 from rafaelportela/master

Reset the state of matrix object using a proper reset method.
Merge pull request #57 from kashban/patch-1

Create about_libraries_def.xml
formatting
update build tools and gradle version
update build tools and target
version bump and changelog update