community/dar: upgrade to 2.7.1
Release notes: https://sourceforge.net/p/dar/mailman/message/37281732/
from 2.7.0 to 2.7.1
- fixed compilation script to require support for C++14 due to new features introduces in 2.7.0 that rely on modern C++ constructions. Updated documentation accordingly about this updated requirement.
- fixed missing included header for compilation to suceed under MacOS X
- fixed typo in man page
- adding minor feature: storing the backup root (-R option) in the archive to be able to restore 'in place' thanks to the new -ap option that sets the -R path to the one stored in the archive.
- merging fixes an enhancements brought by release 2.6.15