Run tests in parallel

I added the `--parallel` command line option to the CTest command. The
jobs value comes from the `cmake.ctest.parallelJobs` setting, the
`cmake.parallelJobs` setting, or the number of CPU cores, whichever
the extension finds first.

closes #31

0.4.0

Fix extension activation

I didn't realize that I need to bundle the extension to use the xml2js
package. I learned how to bundle the extension with webpack and made
all the necessary modifications. Manual tests using `vsce package` and
`code --install-extension` indicate that this solves the problem.

closes #24

0.3.0

0.2.0

0.1.0