* common-src/conffile.c: Add APPEND keyword to tag and dump-selection.
* man/xml-source/amanda.conf.5.xml: Document tag and dump-selection.


git-svn-id: https://amanda.svn.sourceforge.net/svnroot/amanda/amanda/trunk@5215 a8d146d6-cc15-0410-8900-af154a0219e0