graph neighbors on mouseover

an es2015 d3v4 iteration on the block Force layout graph with colour-coded node neighbours from @samuelleach

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First attempt at making a colour-coded graph, with code snippets inspired from the D3 community.

Green => Friend and follower.

Red => Follower

Blue => Friend.

Improvements needed:

1. Smooth transition on the arrow head.

2. Better positioning of the arrow heads.