1055 post cross link (#1077)

* Correct disportionate linkedin share button

* #1055 Post cross links, new styling, new icons, tweak post full footer additional explore menu

* Improved custom steemd/steemdb explore icons

* Use foundation dropdown for better on screen alignment, css updates

* Removed un-needed dropdown component

* Open new window for vetted block explorer links

* Include titles on share item hovers

* Add new chain icon, add to icon list

* New explore component, new dialog, share copy actions

* Refinements to explore reveal modal, copy function

* Tweaks to share this post reveal, more uniformed alt links

* Include permlink in servce record event

* move copy button to the right; adhere to style guide