Avoid input image to be 404

[fritx]

http://fritx.github.io/FEbps/CSSgram-Vuex/dist/
Currently the inputValue and imageSrc change together at an INPUT_CHANGE.

const mutations = {
  [INPUT_CHANGE] (state, value) {
    state.showCamera = false
    state.inputValue = value
    state.imageSrc = value
  },
// ...

export function inputChange ({ dispatch }, value) {
  dispatch(INPUT_CHANGE, value)
}