Write and report coverage data with the 'coverage' package.

Original code by Ross Lawley.

Requires Ned Batchelder's excellent coverage: http://nedbatchelder.com/code/coverage/

command line options

--cover=COVERPACKAGES
(multi allowed) only include info from specified package.
--cover-report=REPORT_TYPE
html: Directory for html output.
report: Output a text report. annotate: Annotate your source code for which lines were executed and which were not.
--cover-directory=DIRECTORY
Directory for the reports (html / annotate results) defaults to ./coverage
--cover-show-missing
Show missing files
--cover-ignore-errors=IGNORE_ERRORS
Ignore errors of finding source files for code.