Added an hint in the readme, that the label must start with an HTML element, so that it is embedded as html
Added an hint in the readme, that the label must start with an HTML element, so that it is embedded as html

ENCODE-DCC/dagre-d3,9n/dagre-d3,git-ashish/dagre-d3,9n/dagre-d3,harsha-mudi/dagre-d3,cbfx/dagre-d3,9n/dagre-d3,cbfx/dagre-d3,cpettitt/dagre-d3,dagrejs/dagre-d3,rwl/dagre_charted,git-ashish/dagre-d3,ENCODE-DCC/dagre-d3,cpettitt/dagre-d3,dominiek/dagre-d3,cpettitt/dagre-d3,cbfx/dagre-d3,rwl/dagre_charted,dagrejs/dagre-d3,dominiek/dagre-d3,dominiek/dagre-d3,harsha-mudi/dagre-d3,rwl/dagre_charted,git-ashish/dagre-d3