Resize the window's content area
Resize the window's content area

Fixes: https://github.com/feross/webtorrent-desktop/issues/565

This was trivial thanks to a new Electron API in 1.3.3

feross/webtorrent-app,feross/webtorrent-desktop,feross/webtorrent-desktop,michaelgeorgeattard/webtorrent-desktop,feross/webtorrent-app,michaelgeorgeattard/webtorrent-desktop,michaelgeorgeattard/webtorrent-desktop,webtorrent/webtorrent-desktop,yciabaud/webtorrent-desktop,feross/webtorrent-desktop,webtorrent/webtorrent-desktop,feross/webtorrent-app,webtorrent/webtorrent-desktop,yciabaud/webtorrent-desktop,yciabaud/webtorrent-desktop