No longer prints -e when DF finishes.

That echo option is a bash-specific extension, unavailable under other shells.
Fortunately, a bare echo with no arguments prints the single newline required here.
Merge remote-tracking branch 'eswald/spurious-e'
Update NEWS.
Merge remote-tracking branch 'dfhack/develop' into HEAD
Update NEWS.
Merge remote-tracking branch 'jjyg/develop'
ruby: add stl-fstream to codegen