installation: moved from setup.py to pyproject.toml:

- updated installation to use the now standard `pyproject.toml` instead of legacy
`setup.py`. `setup.py` and other legacy files have been deleted.
- removed outdated README4PACKAGERS
- removed pylintrc which has not been correctly reviewed. Linter conf should go to
  `pyproject.toml` now.
- [hatch](https://hatch.pypa.io) is now used as main building tool. However, thanks to the
use of standards, other tools can be used too.
- update .hgignore
- several dependencies version bump, with code update to adapt to changes.

pyproject.toml

@@ -0,0 +1,111 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "libervia-backend"
+dynamic = ["version"]
+description = "Libervia: A feature-rich XMPP client showcasing diverse frontends, uniting instant messaging, blogging, file sharing, and ActivityPub-XMPP interactions seamlessly."
+readme = "README.md"
+license = "AGPL-3.0-or-later"
+requires-python = ">=3.7"
+authors = [
+    { name = "Libervia Dev Team", email = "contact@goffi.org" },
+]
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Environment :: Console",
+    "Framework :: Twisted",
+    "Operating System :: POSIX :: Linux",
+    "Topic :: Communications :: Chat",
+    "Topic :: Internet :: XMPP"
+]
+dependencies = [
+    "aiosqlite",
+    "alembic",
+    "babel < 3",
+    "cryptography >= 41.0.1",
+    "dbus-python < 1.3",
+    "html2text < 2020.2",
+    "jinja2 >= 3.1.2",
+    "langid < 2",
+    "lxml >= 3.1.0",
+    "markdown >= 3.0",
+    "miniupnpc < 2.1",
+    "mutagen < 2",
+    "netifaces < 0.12",
+    "oldmemo >= 1.0.0, < 2",
+    "omemo >= 1.0.0, < 2",
+    "pillow >= 6.0.0",
+    "progressbar2 < 3.54",
+    "pygments < 3",
+    "pygobject < 3.40.1",
+    "pyopenssl >= 23.2.0",
+    "python-dateutil >= 2.8.1, < 3",
+    # currently disabled due to incompatibility, OTR feature may be removed in
+    # the close future
+    # "python-potr < 1.1",
+    "pyxdg < 0.30",
+    "pyyaml < 7.0.0",
+    "sat_tmp @ hg+https://repos.goffi.org/sat_tmp#egg=sat_tmp",
+    "setuptools_scm",
+    "shortuuid ~= 1.0.11",
+    "sqlalchemy >= 1.4",
+    "treq < 23.0.0",
+    "twisted[tls] >= 22.10",
+    "twomemo >= 1.0.0, < 2",
+    "txdbus",
+    "urwid >= 1.2.0, < 3",
+    "urwid-satext @ hg+https://repos.goffi.org/urwid-satext#egg=urwid-satext",
+    "wokkel >= 18.0.0, < 19.0.0",
+    "xmlschema",
+]
+keywords = [
+    "XMPP",
+    "chat",
+    "instant_messaging",
+    "blogging",
+    "photo albums",
+    "ActivityPub",
+    "file sharing",
+    "events"
+]
+
+[project.optional-dependencies]
+SVG = [
+    "CairoSVG",
+]
+
+[project.scripts]
+jp = "libervia.cli.base:LiberviaCli.run"
+li = "libervia.cli.base:LiberviaCli.run"
+libervia-backend = "libervia.backend.core.launcher:Launcher.run"
+libervia-cli = "libervia.cli.base:LiberviaCli.run"
+libervia-tui = "libervia.tui.base:LiberviaTUIApp.run"
+primitivus = "libervia.tui.base:LiberviaTUIApp.run"
+sat = "libervia.backend.core.launcher:Launcher.run"
+
+[project.urls]
+Homepage = "https://libervia.org"
+Documentation = "https://libervia.org/documentation"
+Repository = "https://repos.goffi.org/libervia-backend/"
+Roadmap = "https://libervia.org/roadmap"
+
+[tool.hatch.envs.default]
+# we need system-package for GPG
+system-packages = true
+
+[tool.hatch.version]
+path = "libervia/backend/__init__.py"
+
+[tool.hatch.build.targets.wheel.shared-data]
+"i18n/fr/LC_MESSAGES/libervia_backend.mo" = "share/locale/fr/LC_MESSAGES/libervia_backend.mo"
+CHANGELOG = "share/doc/libervia-backend/CHANGELOG"
+COPYING = "share/doc/libervia-backend/COPYING"
+INSTALL = "share/doc/libervia-backend/INSTALL"
+README = "share/doc/libervia-backend/README"
+README4TRANSLATORS = "share/doc/libervia-backend/README4TRANSLATORS"
+"misc/org.libervia.Libervia.service" = "share/dbus-1/services/org.libervia.Libervia.service"
+
+[tool.hatch.metadata]
+allow-direct-references = true