Update `help.sh':
- Update root location for texinfo manuals. Previously they where
under `branches/Manuals/Texinfo' directory structure. Now they are
as other manuals inside `trunk/Manuals'.
I made the former change thinking about unification of manual
formats at trunk/Manuals (i.e., Only docbook manuals at trunk).
Nevertheless that doesn't make too much sence for me now.
Tcar-fs is such a very documentation that development must be at
trunk/ structure. Moreover, branches must be created from trunk
or other branches. They shouldn't stand on their own.