Add optional coloring of task IDs

[dynobo]

Do you want to request a feature or report a bug?
Feature request

What is the current behavior?
Task IDs (the numbers on the beginning of every task) are formated using the default formatting

What is the expected behavior?
Task IDs can be configured to show up in a different color

Which versions todo.sh are you using?

Run todo.sh -V
v2.11.0

Which Operating System are you using?
Arch Linux

Which version of bash are you using?

Run bash --version
4.4.23(1)-release

[iamleot]

Hello dynobo, dynobo writes:

**Do you want to request a *feature* or report a *bug*?** Feature request **What is the current behavior?** Task IDs (the numbers on the beginning of every task) are formated using the default formatting [...]

As a possible workaround I use the following to underline them (in ~/.todo/config): export TODOTXT_FINAL_FILTER='awk '"'"'$1 = sprintf("\033[4m%s\033[0m", $1)'"'"''

[dynobo]

@iamleot:
Nice solution! Works for me, so feel free to cancel my PR and close :-)

[iamleot]

dynobo writes:

@iamleot: Nice solution! Works for me, so feel free to cancel my PR and close :-)

I'm not a todo.txt-cli developer and I think that having a COLOR_ID as you have proposed is handier (and also consistent with other COLOR_* variables!) than adjusting it via TODOTXT_FINAL_FILTER! :)

[dynobo]

@iamleot: okay, I'll leave the PR open, and wait for an opinion by one of the devs :-)