Ada documentation issues

["Joseph S. Myers" <jsm28@cam.ac.uk>]

There are several issues with the documentation of the Ada front end which
need to be resolved:

* The front end should have a proper manual, distributed in the ada
directory.  Once this is done, I will attend to updating
update_web_docs and onlinedocs/index.html to have that manual
available online.

* gcc/doc/install.texi needs updating: both to include ada in the list
of valid --enable-languages values, and to document exactly what needs
to be preinstalled in order to build the Ada front end.  As long as
there is a separate "make gnatlib_and_tools", this also needs to be
documented in install.texi.

* gcc/doc/contrib.texi should have GNU Ada contributors listed.

* gcc/doc/gcc.texi should be updated, both in the chapter "Compile C,
C++, Objective C, Fortran, Java or CHILL" and in "Language Standards
Supported by GCC" (the latter possibly pointing to where the GNU Ada
documentation describes Ada standards and GNAT's relation to them).

* gcc/doc/invoke.texi should have documentation added for suffixes for
Ada source files and for whatever -x language options there are for
Ada.

* Some more GNU Ada maintainers may need adding to MAINTAINERS.

-- 
Joseph S. Myers
jsm28@cam.ac.uk