Fixes #822. Deps.flush hides Error.message.

Prints e.message if e.stack undefined.
Make _renameAlmostAtomically slightly more atomic.

This removes an existence check before a rename, and just tries the rename and
sees if it succeeds.
support github tarballs as dependencies
don't watch warehouse "tools" files for reload
make build-tools-tree more set-e/u
Clean up test-in-console output
Disable the native parser by default.

This was the behavior pre-0.5.8, and prevents some errors from becoming segfaults.
small comment clarifications
dep.depend() instead of Deps.depend(dep)

simpler than having Deps.depend and addDependent, reads fine
fix whitespace
docs wording
Deps.depend past-compat
more whitespace issues
Merge branch 'deps-radical' into devel
Deps History.md
don't shrinkwrap-install things that we're about to (un/re)-install
use alpha1 in run-tools-tests
Make directories in the warehouse contain read-only files.
Skip slow npm-update step for warehouse packages, which should be write-once.
"meteor run" exits on concurrent "meteor update" that would affect it