Add commandline option -lowmem

[shoo]

The -lowmem option is effective when building in an environment with low memory capacity.
When specifying this using dub, it is necessary to describe it in dflags of dub.sdl/.json which is a configuration file now.
However, since this option is not dependent on the project itself, but an option that needs to be switched depending on the building environment, it should not be described in a configuration file that applies regardless of the environment.
To solve this, I propose to allow the -lowmem option to be specified in the command line argument of dub itself.

Thanks!

[rikkimax]

Alternatively use DFLAGS="-lowmem" dub build.

[shoo]

Thanks for suggesting alternatives.
In addition, editing sc.ini / dmd.conf / ldc2.conf has the same effect.

[Geod24]

It sounds like something that should be in the settings file.

[shoo]

Sounds good. It's a good idea to be able to describe it in the settings file.

[Geod24]

Looks like you fixed this, right ?

[shoo]

Yes, this has been released with dmd 2.097.0.