improve thread-based unittest robustness

Use synch points to ensure the poll interval change is effective.
setup.py allchecks; force sys.exit(1) so we fail
bracket test_lazarus with setUp/tearDown
make travis and pep8/pyflakes fail
bump travis.yml; try fixing coveralls output
disable xunit output from nose
fill out docs.sh
add coverage.sh/travis.sh

The former runs coverage analysis, the latter controls what Travis CI
runs.
use travis.sh in Travis CI
clean up test.sh; no coverage, no xunit
towards #8
towards #8
disable coverage in Travis CI
Merge branch 'experimental'

Conflicts:
	README.rst