Fix onstart timing

When using streamPages, onstart is now called before any ondataavailable pages are fired.

Deprecate Bower

• Deprecate Bower support
• Replace maxBuffersPerPage config option with maxFramesPerPage
• Fix issue where encoder could output empty pages if buffer size was less than one frame.

Minor Enhancements

• Run some async tasks in parallel for minor performance improvements.
• Fix dependencies error for sinon-chai
• Use arrow functions instead of self

Libopus 1.3 + Lower latency

• Update Libopus to version 1.3
• Decrease streaming latency by delaying recording until worker is fully initialized

Better Behaviour

This release should help with incoming changes to chrome: https://developers.google.com/web/updates/2017/09/autoplay-policy-changes#webaudio
As well as iOS compatability.

• Remove option leaveStreamOpen
• Init the context and worker on start
• Fix worker staying active even when not needed.

Fix serial

Math.random() does not include 1

Fix Serial Number Distribution

• Fix the distribution of serial numbers using round instead of floor

Fix for serial number and granulePos

• Fix issue where serial number range was 0 to 2^32 instead of 0 to 2^32 - 1
• Fix issue where granule position was not set correctly into 64 bits when negative
• Fix issue where granule position was not set correctly into 64 bits when value is 2^32 - 1

Fix bug in wave recording

• Fixed issue in wave recording where converting from float to int incorrectly
• Added some options to example
• Upgrade emscripten to 1.38.1
• Upgrade some dev dependencies

Recording Gain

• Added recording gain option
• Updated emscripten to 1.37.33