jobserver: fix rare race condition in previous timer-exception workaround.

Fix typo in docs: "an C" should be "in C"

fix typo / grammar in docs landing page

Fix typo.

jobserver.py: _try_read()'s alarm timeout needs to throw an exception.

jobserver.py: fix very rare python3 failure reported by a user.

t/110-compile: remove hard dependency on /usr/include/stdio.h.

Merge branch 'doc_install_sudo' of git://github.com/BlameJohnny/redo

Merge: Add compatibility to Python 3 (and retain Python 2)

docs/cookbook/c: missing quote char.

GettingStarted.md: Add -E option to sudo to preserve environment

Remove python<3.0 restriction in setup.py

Make compatible to BeautifulSoup4

Accept octal representations of Python 2 (0nnn) and Python 3 (0onnn)

Prevent iterator being changed while iterating