Incompatibility with other scripts that use `bash-preexec`.

[qbouvet]

bash-timer is incompatible with other scripts that use bash-preexec, for instance undistract-me.

This is because bash-timer defines variables prexec and precmd. Either these variables are already defined, and bash-timer overwrites them, or bash-timer defines them, and whichever bash-prexec script sourced afterwards overwrites them.

The solution to this issue is to use the array functions provided by bash-preexec. I made pull request #2 to that end (and I plan to open a similar pull-request for undistract-me).

Also, thanks for your script I really like it :)

[hopeseekr]

Merged! Thank you so much!!!