Fix distcheck-hook to handle [type: ] prefixes in POTFILES.in properly

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23399 57a11ea4-9604-0410-9ed3-97b8803252fd
Don't distribute files generated by configure

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23400 57a11ea4-9604-0410-9ed3-97b8803252fd
Remove some redundant variable definitions in Makefile.am

These are set automatically via AC_SUBST in configure.ac

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23401 57a11ea4-9604-0410-9ed3-97b8803252fd