Since we were having issues with this in the past, see e.g. [1], add
some verbose information to ease debugging in the future.
[1] https://github.com/appveyor/ci/issues/1342
windres is not always present whereas goversioninfo is easy to install.
This also fixes the generation of resource.syso to be part of the
standard build script instead of only the AppVeyor CI build.
Finally, adapt update-version.sh to patch versioninfo.json.
This fixes the display of the application icon in Windows' uninstall
dialog and allows Inno Setup to use the version information from the
executable.
Note that AppVeyor has windres.exe in all these locations:
C:\cygwin\bin\windres.exe
C:\cygwin64\bin\windres.exe
C:\MinGW\bin\windres.exe
C:\mingw-w64\i686-5.3.0-posix-dwarf-rt_v4-rev0\mingw32\bin\windres.exe
C:\msys64\mingw32\bin\windres.exe
C:\msys64\mingw64\bin\windres.exe
C:\msys64\usr\bin\windres.exe
C:\Qt\Tools\mingw482_32\bin\windres.exe
C:\Qt\Tools\mingw491_32\bin\windres.exe
C:\Qt\Tools\mingw492_32\bin\windres.exe
C:\Qt\Tools\mingw530_32\bin\windres.exe
C:\Ruby193\DevKit\mingw\bin\windres.exe
C:\Ruby23\DevKit\mingw\bin\windres.exe
C:\Ruby23-x64\DevKit\mingw\bin\windres.exe
But only the Ruby versions work without giving an "preprocessing failed"
error.
AppVeyor now has Go and Git for Windows 2.x installed by default. Also, we
can tell MSYS to actually create symbolic links. Finally, let the CI
create the installer, too.