* boost_build_v2.html: Document new option.
* new/generators.jam (find-viable-generators): Revert part of Dave's
commit, essentially disabling finding base type generators.
This part breaks a test, and need to be thinked about.
* new/errors.jam: Handle "--no-error-backtrace" option.
* test/project_test4.py: Adjust for new error syntax.
[SVN r16233]