v4.0.0

• all color options now accept a canvas fillstyle value (a hex or rgb(a) color, a canvas gradient or a canvas pattern) and got renamed accordingly, check out the readme for details about fill style values
• fixed a bug where default layout options would not be overwritten by new options
• the click callback interface got renamed to IWaveClickCallback for consistency
• the core options interface got renamed to IWaveCoreOptions for consistency
• updated the example to the reflect the changes mentioned above and make use of the new fill style