Merge branch 'jk/config-path-include-fix' into maint

include.path variable (or any variable that expects a path that can
use ~username expansion) in the configuration file is not a boolean,
but the code failed to check it.

* jk/config-path-include-fix:
  handle_path_include: don't look at NULL value
  expand_user_path: do not look at NULL path

diff --cc config.c
Simple merge

diff --cc path.c
Simple merge