Disown call terminated other background tasks

Fixes #28
Run the async_run and disown in a subshell to suppress Done output
revert
async_run and disown in subshell when calling to suppress Done output
Merge pull request #31 from ogr3/master

Run the async call and disown in the same subshell

Thanks, looks ok to me. This should fix #30
Show number of stash entries in bash prompt