Drop the custom NewDelegateFontHandle that built our own FontAwesome
atlas slot and reuse Dalamud's UiBuilder.IconFontFixedWidthHandle
instead. One less delegate-build step in the ctor, and the handle is
host-managed so Dispose() leaves it alone.
The pre-cycle icon inventory verified that every site we push the
FontAwesome font for renders an icon that is present in the host's
fixed-width handle glyph range, so no rendering site changes.
JonKazama-Hellion
2315f10d91