Add install-/build-ifcopenshell.py, deprecate corresponding .bat files

Mainly drop-in replacement for `build-ifcopenshell.bat` with `--help`, kw args and args validation, but there's a small caveat.

Previously it was possible to pass args to the underlying build tool as simple positionals - e.g. `build-ifcopenshell vs2022-x64 Release /p:Foo=bar`.
This behaviour is disabled now, because it doesn't allow validating provided args - it's impossible to tell whether `--config Release` is meant to be passed to msbuild or was meant as `--build-cfg Release` for `build-ifcopenshell`.

But it's still possible to pass args to msbuild by using `--` - `python build-ifcopenshell.py vs2022-x64 Release -- /p:Foo=bar`

`install-ifcopenshell.py` is now just a small wrapper passing `--target INSTALL` arg.

src/ifcopenshell-python/docs/ifcopenshell/installation.rst

@@ -240,13 +240,13 @@ C++ Build Tools <http://landinghub.visualstudio.com/visual-cpp-build-tools>`__).
    Only) to deploy the headers and binaries into a single location if
    wanted/needed.
 
-   Alternatively, one can use the utility batch file(s) to build and install the
+   Alternatively, one can use the utility script(s) to build and install the
    project easily from the command-line (installing a project will build it
    also, if required):
 
    .. code-block:: bat
 
-        install-ifcopenshell.bat
+        python install-ifcopenshell.py
 
 .. seealso::