[release-info] Cleanup whitespace.
[release-info] Add release-product-identifier.

This is a lowercase, no whitespace version of the product name.
It is useful for directory names on Unix where spaces and capital
letters are typically not expected.
[build-system] Remove commented out exports.
[build] Move build scripts to their own directory.

This removes the build scripts from the 'lib' directory and places
them in a more appropriate 'share/opendylan/build-scripts' directory
(on Unix, on Windows, the path is just 'build-scripts') under the
installation target directory.

In the future, we may consider moving config.jam to a different
directory as it can contain architecture-dependent information.
[build-system,docs] Document the variables passed to Jam.

This also updates a number of URLs to point to the right locations.
[build-system,docs] Remove mention of mingw.

We don't actually provide such a file.
Merge pull request #824 from waywardmonkeys/move-build-scripts

Move build scripts