Window does not resize

[ltfschoen]

Merging #332 introduced a bug that prevents the window from resizing when you change between pages.

See error message below:

I've already investigated the issue and found that it occurs in fether-electron/src/main/app/messages/index.js upon an 'app-resize' event, where the args[0] value may be a float value, and because we use that value to set the new height of the window, it causes an error, because we pass the value as an argument to setContentSize https://electronjs.org/docs/all#winsetcontentsizewidth-height-animate, which only accepts integers arguments for width and height.