find_mongo_pids: Fix regression in 203a82d.

Don't consider "ps" stderr to be an error. This occurs on OSX Mountain Lion if
DYLD_LIBRARY_PATH or a similar env var is set, and is harmless.

Follow-up to 26c725 to work on more browsers.

Windows Safari (eg) seems to apply the "uncheck existing radios when new radios
are created" even earlier than other browsers, so save values earlier.

History.md update for 0.5.2.

Follow-up to 426a72f: make sure loggingIn goes away in the case of a …

…half-complete login method.

More concepts updates.

Increment version to 0.4.2.

Work around Node 0.8 brokenness with using /dev/stdin in subprocesses.

Bump version number for release.

Bump version number for release!