Add orbcalculator recipe.

Add OrbCalculator https://gitlab.redox-os.org/redox-os/orbcalculator recipe. After the merge is finished the old calculator of OrbUtils should be removed from OrbUtils and OrbCalculator should be added to launcher.

recipes/calculator/recipe.sh

+GIT=https://gitlab.redox-os.org/redox-os/orbcalculator.git
+BRANCH=master