Makefile: rename target 'searx.brand' to 'buildenv'
Makefile: rename target 'searx.brand' to 'buildenv'

And add 'buildenv' as an first order prerequisite to the main targets:

- install
- run
- docs
- docs-live
- project
- node.env
- docker
- test

Signed-off-by: Markus Heiser <14dfd67dd72e7ac80c040b62bb932f1e121795cc@darmarit.de>

asciimoo/searx,asciimoo/searx,asciimoo/searx,dalf/searx,asciimoo/searx,dalf/searx,dalf/searx,dalf/searx