Fixing a possible path issue for IE9.

Being explicit by trashing an exception if data can't be determined from the input argument.
Merge pull request #9 from bbcrd/fix-9

XMLHttpRequest is not handled properly in `WaveformData.create` with IE9
Version 1.1.2
Added normal array & for loop in offsetValues

Replaced dense array in `offsetValues` function to use a normal array
and for loop to prevent the call stack from exceeding it’s limit.
Removed unused karma plugins (breaking the build).
Merge pull request #16 from JonKoops/master

Added normal array & for loop in offsetValues
v1.1.3
Added Points Interface
Merge pull request #19 from chainlink/only-points

Added Points Interface
Updated documentation for the Point object.
Added back testling CI.
Added WaveformDataPoint documentation.
Dist source is now mangled to compress even more.
v1.2.0
web audio wrapper