Preserve order of properties in PropertySet.
Check setpgid return value in parent and child.

A user is having trouble with calls to setpgid failing
with EPERM and we're not sure whether it's the call to
the parent, or child process that is the source of the
failure.  Add check with explicit indication whether
the parent of child failed.
Make setpgid checks non-fatal.

Comment out the call to exit following a failed
called to setpgid.  Can re-enable in the future.
Modernize HTML docs.
Drop "V2" from documentation title.
Add local copies of docbook images.

This permit to build documentation, and have it work
standalone.
Add support for abbreviated paths.
Print the actual values rather than a pointer to a function.
Property comparisons should be comparing feature names not feature instances.
Fix undeclared variable.
Add support for version.
Detect the intel compiler in the environement.

The mentioned 'standard' path were quite old (9.0, last Intel
compiler version is 15.x as on Oct 2014). Keept the legacy
detection though.

Build in 64 bit (seems more common).
Remove outdated HTML pages.
Add a script for building documentation.
Initial integration of tutorial from Boris Schäling.
Change tutorial license to BSL, by Boris' permission.
Improve layout of tables in tutorial.
Replace "bjam" with "b2".
improve tutorial a bit

Rewording/grammar.
Part of it is out of date (such as 'v2' directory).
Minor copy-edits.