Editor UX - Save user history to localStorage on emulation run

[LironHazan]

It will improve development experience if we'll save the cpp code every time the user hits "run simulation".

I suggest adding a tiny util which abstracts (safely) the localStorage.addItem and localStorage.removeItem. state machine: check if there's a localstorage entry: yes: remove it and add a new one. No: add one.

** see TS playground as a reference.

[urish]

It's worth adding a "Revert code" button (or similar) that removes the localStorage code and loads again the initial sample code

[LironHazan]

@urish will do