Document know shortcommings

[Nortamo]

Better documentation for known issues:

• sys.prefix vs sys.base_prefix
• harcoded interpreter path for shebang breaks some scripts (e.g snakemake)
• bin <-> _bin switch requires top level mount which means that some test run under an installation directory like /appl which is not mounted fails, but this is ok. As the program is not going to be run when in /appl, fix is to mount /appl` but this has not been done as to avoid calling broken installations in isolated environments
• Interacting with poetry does not seem to work, needs more testing.
• Unclear if venv installation behavior with adding new jupyter kernels is a bug