Don't touch all files to recompile everything on Makefile changes

[essen]

It should be possible to have a single temporary file as a dependency to all others and use that to force the rebuild of everything, rather than touch everything. Perhaps the .app file can be used for this? If it's touched to 000 it should rebuild all of it. To be experimented with.

[essen]

This ticket is about the "recompile everything when the Makefile changes" in case that's not clear. It currently has to touch all source files to accomplish that and that's not optimal. I'll edit the title.

[essen]

There's a makedep/depend step that generates a .d file with those dependencies.

[crownedgrouse]

thanks , see it now. I removed unrelated posts. feel free to do the same to clean the issue

[essen]

#881 has a solution for doing this properly. /cc @dumbbell

[essen]

Involves changes in core/erlc, plugins/erlydtl and plugins/protobuffs.