Use `$EPOCHREALTIME` (or `$SECONDS`) built-in variable provided by Bash instead of `date +%s`. We're only measuing the difference in seconds, so avoid both the binary invocation as well as the subshell.
Alsö, Reduce environmental pollution by not exporting every variable, and unsetting when done.
Change variable names to match lib/command-duration
Remove `preexec_return_notification()` in favor of `lib/command-duration`'s `_command_duration_pre_exec()`.
This should now use the same preexec hook and variables as the theme library `command_duration`.
tests: handle nanoseconds
For testing non-core files, just `load ../test_helper_libs` after `load ../test_helper` instead of trying to guess which libs must be loaded, in which order, for testing to succeed.
`_command_exists` spews log messages, so our test log is littered with `_log_debug not found`. This fixes that too.
Added a vendored lib loading routine in bash-it.sh
Added documentation on how to vendor libs in bash-it
Added and fixed plugins using preexec
Added tests for two plugins
Removed the old preexec lib
