Reworked localStorage functions.

Reworked localStorage functions to behave more like GM_[g/s]etValue.
Changed/fixed UI functionality.

Added dragging and resizing UI and functionality. Fixes #2
Moved "reset popularity" button to new dedicated bottom section.
Added Github repo link to bottom section.
Fixed Chrome width not being the full width of the chat.
Reduced size of emote grid (no fixed height, still fixed width).
Reworked functionality of popup: when first opening, behaves normally;
when resized or dragged, does not close unless "open" button is clicked
again.
Reworked custom scrollbar. Now if Twitch scrolls do not work, will
automatically use a working one.
Version bump