Lower minimum window size to accomodate smaller displays

[4194304]

In Pixelorama, it has display scale options for lower scale displays (such as 0.5 and 0.75), but actually using the program on low resolution displays is a chore. The scaling works perfectly fine, but the huge minimum window size makes using the program a horrible experience. This minimum display size of 1024x576 makes the program not fit on screen resolutions such as 960x540, 640x480, 720x480, among others. For bigger screen sizes such as 1024x768, 1280x720, and also 1366x768, this minimum size will occupy most of the working screen space that the user has, even though with a lower scale the program does not need to do that.

What should be done here:
Lower the minimum size to something like 320x200.

TLDR: Decrease the minimum window size to accommodate smaller display sizes with smaller scaling.

[OverloadedOrama]

Implemented in de3ff4c, the new minimum window size is 320x200.