run document test failed about scons

[bdbaddog]

To do the doc build you'll also need to install a handful of system packages.
There's a script to do so, but it may be out of date.
try running bin/scons_dev_master.py building

[mwichmann]

To set up to "do everything" (be able to construct the SCons package and/or docs), use the requirements-pkg.txt; to "develop" SCons use the lighter-weight requirements-dev.txt (the former includes the latter). The base requirements.txt is for using SCons, but not for hacking on SCons; it has no actual dependencies listed (this is actually documented someplace, but we don't expect SCons learners to need to build the doc set, so it's not in the user guide).

And yes, there was a transitional period when either the stdlib xml or the external lxml could be used, but the xml-only approach stopped working. A cleanup is in order, but there are lots of things that need attention.

[bdbaddog]

re email. The host is moving from one machine to another, so this may be a glitch caused by that.