* center the title on full screen modals.
Adding the `[dir=“ltr”]` atttribute to the css rule for a child style didn’t work the way I expected.
`[dir="ltr"] .full-screen .header-item-title` did not match the fullscreen title element, so the style wasn’t applied.
`.full-screen [dir="ltr"] .header-item-title` did match.
* fix the filter to reverse the icon and ‘x’ in the filter input
* more space after the library back icon
* reverse the arrow on camera -retake image and rerecord sound.

* Export initial states for each reducer
* combine all gui reducers (excludes scratchPaint and intl)
* combine all initial states to create default guiState for preloading in www
* expect all of the gui state to be accessible at `state.scratchGui`

Fixes #993