Added section base and length symbols to lwlink Added the ability for a link script to define section base and section length symbols when linking. These symbols are searched for when an external reference is resolved before looking up any symbols in the various objects being linked. Also documented the new link script directives and added such directives to all default link scripts.

See the file GPL3 for a copy of the GNU General Public License, version 3,
under which the majority of this distribution is licensed.

Some specific source files, including many of those in the lwcc subdirectory
are licensed differently. See each individual file for specific details.