Node.js agent v2.2.2

Bug fixes

• Hapi handlers will now preserve the defaults associated with them.

  Previously when wrapping handlers, the agent would drop the associated defaults on the ground, these are now properly forwarded to the wrapper. Big thanks to Sean Parmelee (@seanparmelee) for finding the root cause of this bug and reporting it!

• Fixed starting the agent with an invalid process version.

• Pinned request version for testing old versions of Node.

• Added tests for feature flags created at agent initialization.