This being the first 3rdparty-contribution, we may want to consider the
structure of the project file generation scripts. Perhaps add small,
constribution-specific scripts to each directory in 3rdparty instead of adding
all constraints to generate_visualc_files.pl?
Running the generation script with "include_crypto" input parameter set to 1
makes the mbedtls sources being overshadowed by crypto sources.
In case of any duplicate sources, crypto ones take precedence.
Add a function that deletes all the old Visual Studio prokect files
before generating the new ones. This ensure that project files for
delete example applications are removed from the repository.