Cleanup and standardize omnibus-software definitions

`make install` should also run with `env: env` as well.

it likely works most of the time, but you can get into situations where changing flags triggers 'make install' to actually kick off compiles and re-build it differently from what was intended.   those are largely buggy Makefiles, but the expected 'API' should mimic:

```bash
export CFLAGS="yadda yadda"
./configure
make
make install
```

So, all three commands are expected to get the same environment variables, always.