cmake: corrected build issues on windows

corrected a problem when looking for the awk program when using Git for
Windows, which has the program named qawk and a shell script named awk
(the awk script does not work with the MinGW cmake generator) - the
cmake build file now looks for gawk first

corrected problems when copying the test files on Windows when using
the MinGW Makefiles generator within Qt Creator, which uses cmd.exe
instead of MSYS:sh when using the MSYS Makefiles generator - different
make directory and copy commands are required, and file paths need to be
converted to back slash windows format with surrounding double quotes
cmake: corrected build issue with enums.awk and windows sort

the "-d" option was added to the sort command called from the enums.awk
script so that it would ignore "_" underscore characters in the names of
the codes; however, on Windows with the MinGW generator, the Windows
sort command is called, which does not support this option (options
start with a forward slash); unfortunately this option doesn't work as
desired anyway, so it was removed