Track and report code coverage for your package and (optionally) upload
the results to a coverage service like 'Codecov' <http://codecov.io> or
'Coveralls' <http://coveralls.io>.
Code coverage is a measure of the amount of code being exercised by a set
of tests. It is an indirect measure of test quality and completeness.
This package is compatible with any testing methodology or framework and
tracks coverage of both R code and compiled C/C++/FORTRAN code.
