add gradle files
ignore local gradle files
add gradle wrapper, issue #126
ignore build dir
include crouton dependency
don't abort check task on lint errors
compile with JDK 1.7
convert switch with android resources to if-else, see http://tools.android.com/tips/non-constant-fields
enable unit tests
run gradle tests on Travis
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Currently translated at 95.7% (68 of 71 strings)
ignore *.swp file (temporary files of vim)
add initial CircularAverage class
test average value after a step is applied
test for negative step
move check for initial state to generic method
normalize angles
normalize expected angles
normalize setpoint
fix coding style : variable name