Update changelog to 2.4.0
Revert "Merge pull request #472 from jimmyhchan/OPP"

This reverts commit dcc3d350214ab270bffe3a957f3b438b429651b4, reversing
changes made to ad2d39fd4f2e29223d27b94a19512f2bab45d05e.
Merge pull request #493 from prashn64/changelog

Update changelog to 2.4.0
Merge pull request #494 from sethkinast/revert-prototype-lookup-prevention

Revert "Merge pull request #472 from jimmyhchan/OPP"  This will allow dust references to look up the object's prototype chain again.
Release v2.4.1
Don't swallow errors from helpers; output them to the chunk
Tests that test errors match substrings instead of testing equality of error messages.

This allows tests that throw different errors in PhantomJS vs a browser to pick a commonality and test on that instead of the exact error message.
Pin NPM@1.4 for Travis
Merge pull request #495 from sethkinast/catch-helper-errors

Catch syntax errors in context and fail gracefully
Upgrade to pegJS 0.8

Upstream changes that affect us:
 - line and column variables are now functions
 - parser.toSource() removed in favor of a generator option that switches between an object and string versions
Grammar cleanup. Use new |error| grammar.
Upgrade pegJS to 0.8
Grammar cleanup. Use new |error| grammar.
Release v2.3.6
Merge 2.3 changes
Merge pull request #497 from sethkinast/pegjs-0.8

Upgrade to pegJS 0.8
- This change corresponds to a 90% reduction in template compile time.
Release v2.4.2