add missing service_config.mho fixture
remove absolute shebang lines on all gup scripts
add tools/gup.cmd
fix build on windows

 - add gup.exe
 - use relative paths to sjs and conductance in build scripts
docs: fix ObservableVar::modify example code
add linux_x86 install bundle
fix a bunch of build scripts which didn't run on windows
fix install.sh platform / architecture logic
update gup