Remove documentation files which are generated by the build

This change removes the HTML and CHM documentation files from source control, and adds the corresponding folders to `.gitignore`. I believe this is a reasonable change for the following reasons:

1. The files can be generated by a quick build of the documentation project.
2. The files are not being updated on a regular basis. There are two folders containing the HTML documentation yet only one is the target of the documentation build.
3. The next release of the SDK can include a binary download of the compiled help, similar to the way the SimpleRESTServices library provides SimpleRESTServices.chm as a download [in the v1.1.0.0 release](https://github.com/JSIStudios/SimpleRestServices/releases/tag/v1.1.0.0).