Integrate PROMPT_COMMAND uploading by @evverx

[eleweek]

This should work a lot better than bash-preexec(it seems that the only problem is that command is uploaded AFTER its completion).

https://gist.github.com/evverx/695129199b5c7f4d0f94#file-bulletproof-history-collector-bash-L32

Thanks to @evverx