test documentation: update wording, generate test manual page (closes #734)
tarball generation: include config.h.in, set mode and ownership

Include config.h.in as well as configure.

Also sets correct owner, group and mode for all appended files.

Update the mtime of all appended files so that configure and config.h.in
are always newer than configure.ac.

(Fixes many problems introduced by 5023ade7, and makes the commit
message actually true.)
document new bindings introduced in cd1c2f74d3bc