new property for changes in option for runtime only

- new property in Espruino.Options.optionfields named onBlur
- added blur event if for all optionFields where onBlur is true
- added eventhandler callOnBlur to set options from formular directly to
running session (see general.webCamOn)
- function setOptionsFromForm into 2 functions to make single field call
accessible
- function optionsOnLoaded into 2 functions to make single field call
accessible