feat(inputs.directory_monitor): Improve internal stats

[Hipska]

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This to better distinguish between 2 directory_monitor instances and the files they processed/dropped.

[Hipska]

Please also check 6bedf62 if that would be accepted or if I need to rollback/change..

[srebhan]

Wouldn't this break existing queries as they now need to accumulate over all directories?

[Hipska]

Hmm, correct. Do you suggest to have both metrics then (1 with and 1 without the directory tag)?

[srebhan]

@Hipska yeah maybe add new metrics with a "per dir" suffix or similar...

[telegraf-tiger]

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Artifact URLs

DEB	RPM	TAR GZ	ZIP
amd64.deb	aarch64.rpm	darwin_amd64.tar.gz	windows_amd64.zip
arm64.deb	armel.rpm	darwin_arm64.tar.gz	windows_arm64.zip
armel.deb	armv6hl.rpm	freebsd_amd64.tar.gz	windows_i386.zip
armhf.deb	i386.rpm	freebsd_armv7.tar.gz
i386.deb	ppc64le.rpm	freebsd_i386.tar.gz
mips.deb	riscv64.rpm	linux_amd64.tar.gz
mipsel.deb	s390x.rpm	linux_arm64.tar.gz
ppc64el.deb	x86_64.rpm	linux_armel.tar.gz
riscv64.deb		linux_armhf.tar.gz
s390x.deb		linux_i386.tar.gz
		linux_mips.tar.gz
		linux_mipsel.tar.gz
		linux_ppc64le.tar.gz
		linux_riscv64.tar.gz
		linux_s390x.tar.gz

[srebhan]

I don't think re-registering the metric would be a good way for backward compatibility...

[srebhan]

Looks good to me. Thanks @Hipska!