use build status icon of master branch [skip ci]
enable coverity addon, issue #146
add coverity badge, issue #146 [skip ci])
Revert "upgrade cobertura-maven-plugin to 2.6"

2.6 is not compatible junit4/robolectric

This reverts commit 215e10ed5716e7255490a9c36abe768e28a9743e.
check if shortest path will cross min or max, issue #147
add a few more tests, issue #147
fix description
CID 60865 : fix Coverity issue : dereference null return value
test steps into each quadrant, add constants, issue #147
test negative steps into each quadrant, issue #147
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Merge remote-tracking branch 'origin/master'
itemize encrypted environment variables
add tests crossing maximum, issue #147
add tests crossing minimum, issue #147
check if buildtime-trend dir exists before cloning, otherwise update git repo
refactor code to fix CID 60865 : dereference null return value
enhance test to fix Coverity issue CID 60867 : EC: Comparing incompatible types for equality
refactor code to fix CID 60865 : dereference null return value
add test applying 180° step, issue #147