PRE_CALCULATED_IFS avoids use "echo" in _lp_set_prompt()
Test if LP_OLD_PROMPT_COMMAND isn't empty before eval.
Correct bug in hg_status.
Remove useless echo.
Remove useless echo.
Reduce gap between my version and the official one.
Simplify load estimation.
Ensure LP_MARK_DEFAULT encapsulation.
Simplify PS1 calculation.