docs(state): add readme to state package
docs(state): add readme to state package

cyclejs/cyclejs,cyclejs/cycle-core,ntilwalli/cyclejs,staltz/cycle,ntilwalli/cyclejs,cyclejs/cycle-core,ntilwalli/cyclejs,cyclejs/cyclejs,ntilwalli/cyclejs,staltz/cycle,cyclejs/cyclejs,cyclejs/cyclejs