cmds.distro: Move all modules to lib

Functions abstracting the distribution are not only needed in the
context of the distro subcommand, but also by other code, so make the
bulk of the code abstracting the distribution available in some place
more universally useful than below cmds.distro.

This commit leaves the source files mostly unchanged. They are only
patched to fix import paths, so that functionality is preserved.
Refactoring the code from command-line API to library API will be
done by the next commit.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/lib/distros/BePkg.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+
+from __future__ import annotations
+from typing import Iterable, TYPE_CHECKING
+
+import abc
+
+from ..Package import Package
+from .Backend import Backend as Base
+
+if TYPE_CHECKING:
+    from ..Cmd import Cmd as Parent
+
+class BePkg(Base):
+
+    def __init__(self, parent: Parent):
+        super().__init__(parent)
+
+    async def files(self, name: str) -> Iterable[str]:
+        return await self._files(name)
+
+    @abc.abstractmethod
+    async def _files(self, name: str) -> Iterable[str]:
+        pass
+
+    async def meta_data(self, names: Iterable[str]) -> Iterable[Package]:
+        return await self._meta_data(names)
+
+    @abc.abstractmethod
+    async def _meta_data(self, names: Iterable[str]) -> Iterable[Package]:
+        pass