* Add support for Alexey Tourbin's QSORT code

See https://github.com/svpv/qsort

* Add benchmark scripts and compilation mode

Compile with `make O_BENCHMARK=1`, and run benchmarks with e.g.:
  ./misc/test/benchmark.sh ./nnn '/' '/usr/bin' '/usr/lib' > benchdata
You can then plot basic violin graphs with:
  ./misc/test/plot-bench.py benchdata

* Update style, doc, haiku support, fix lint

* Add icons

* Fix build break

* Fix icon position in detailed mode

* Various fixes

* Provision for icon specific colors

No icons with oldcolor. Small optimizatons

* Update Makefiles

Small refinement for other matching

Note that this is not compatible with 4 contexts.

* Add support for Haiku OS

* Adjust DISTFILES and dist rule in haiku

* Don't pack sources (github does it better), sign sources

* Make CircleCI generate the same git archive as Github, return make dist

* Revert make clean too

* Upload signature to Github release

* Read Github token from an env variable

Use only the `strip` target fort stripping the binary.

$(CP) is not set by GNU Make
Seems like [1] is a full list of what GNU Make defines implicitly
[1] https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html

Mistook CPPFLAGS ("C preprocessor flags") for CXXFLAGS ("C++ flags").

This reverts commit 0956b82d33.