tracee: a new makefile is born

Original Makefile will be kept until all targets, release process and
docker container functionalities are in place. The new Makefile(s) are
meant to be used by:

    $ make -f Makefile.new <target>

The new Makefile targets are:

    $ make env                  # show makefile environment/variables
    $ make reqs                 # verify build requirements

    # build

    $ make all                  # build tracee-ebpf, tracee-rules & rules
    $ make bpf-core             # build ./dist/tracee.bpf.core.o
    $ make bpf-nocore           # build ./dist/tracee.bpf.XXX.o
    $ make tracee-ebpf          # build ./dist/tracee-ebpf
    $ make tracee-rules         # build ./dist/tracee-rules
    $ make rules                # build ./dist/rules

    # clean

    $ make clean                # wipe ./dist/
    $ make clean-bpf-core       # wipe ./dist/tracee.bpf.core.o
    $ make clean-bpf-nocore     # wipe ./dist/tracee.bpf.XXX.o
    $ make clean-tracee-ebpf    # wipe ./dist/tracee-ebpf
    $ make clean-tracee-rules   # wipe ./dist/tracee-rules
    $ make clean-rules          # wipe ./dist/rules

    # test

    $ make test                 # run all go & opa tests
    $ make test-tracee-ebpf     # go test tracee-ebpf
    $ make test-tracee-rules    # go test tracee-rules
    $ make test-rules           # opa test (tracee-rules)

Note: DO NOT mix usage of ./Makefile, ./tracee-ebpf/Makefile &
      ./tracee-rules/Makefile with ./Makefile.one. Make sure to wipe
      all "dist" directories before using Makefile.one.