net-mgmt/cacti: Update to 1.2.8

• Sort pkg-plist to make future patching/comparing easier.

While I'm here:

• Use ${COPYTREE_SHARE} to correctly install a whole set of files instead of using "cp -R".

• Also remove a very outdated test was required when updating to the 0.8.7a release of net-mgmt/cacti. It was introduced +12 years ago in r203859 and is no longer required nowadays.

Changelog:

https://github.com/Cacti/cacti/releases/tag/release%2F1.2.8

PR: 242834
Submitted by: Michael Muenz <m.muenz@gmail.com> (based on)
Approved by: maintainer timeout (14 days)
MFH: 2020Q1
Security: 86224a04-26de-11ea-97f2-001a8c5c04b6