[new] editors/helix version 22.08.1

Hi,

this is a port for Helix (text editor) https://helix-editor.com

Features:
- Vim-like modal editing
- Multiple selections
- Built-in language server support
- Smart, incremental syntax highlighting and code editing via
tree-sitter

It's my first port for a Rust tool. Tested on amd64, works fine.

- Makefile defines MASTER_SITES to download helix-22.08.1-source.tar.xz
: full sources (Helix + TreeSitter grammars)
- Special case with EXTRACT_CASES to decompress sources in WRKDIST

- Patches (derived from those of the FreeBSD port
https://github.com/freebsd/freebsd-ports/tree/main/editors/helix/)
* patch-helix-term_build_rs: remove Git hash in internal version
* patch-helix-loader_src_lib_rs: define path for data directory
(${PREFIX}/share/helix)
* patch-helix-loader_src_grammar_rs: disable internal command 'hx
--grammar fetch' to fetch TreeSitter grammar with Git

- Install tutor.txt, themes, queries and grammars (.so files built from
TreeSitter sources) in ${PREFIX}/share/helix/runtime


Port also available on GH openbsd-wip
https://github.com/jasperla/openbsd-wip/tree/master/editors/helix


comments welcome, Laurent