Add icons to gatsby-plugin-manifest example options (#1140)
Add icons to gatsby-plugin-manifest example options (#1140)

* Add icons to example options, mention the "static" directory

* Fix path to 'static' folder

chiedo/gatsby,Khaledgarbaya/gatsby,fk/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby,mickeyreiss/gatsby,chiedo/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,mickeyreiss/gatsby,fabrictech/gatsby,fabrictech/gatsby,gatsbyjs/gatsby,Khaledgarbaya/gatsby,mingaldrichgan/gatsby,danielfarrell/gatsby,ChristopherBiscardi/gatsby,mingaldrichgan/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,fk/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,mickeyreiss/gatsby,okcoker/gatsby,chiedo/gatsby,Khaledgarbaya/gatsby,fk/gatsby,0x80/gatsby,gatsbyjs/gatsby,okcoker/gatsby,0x80/gatsby,danielfarrell/gatsby,okcoker/gatsby,danielfarrell/gatsby,fabrictech/gatsby