v4.0.2

What's Changed

• V4 - feature merge by @nswamy14 in #78
• updated rollup config; updated examples by @nswamy14 in #79
• updated package.json; removed unwanted packages by @nswamy14 in #80
• updated v4 gitbook link by @nswamy14 in #81
• PDF capability added to canvas layer
• canvasNodeLayer API discontinued; Created separate node package : node-i2djs
• Canvas/SVG/Webgl Layer api bug fixes
• Updated Examples