Revised the location queries for determining if a window contains a given point

[brainwater]

I have addressed the points raised in #20 (original pull request was #15). The default coordinates used are based on the active monitor, however there is a boolean xml attribute "global" that can be added to the containsxpoint and containsypoint queries in order to treat the points as global coordinates, not just for the active monitor.

With an asymmetrical monitor setup (e.g. a 4k screen next to a 1080p screen, like my current setup at work) the global coordinates would be less useful in my opinion, however with symmetrical setups of monitors (e.g. 4 1080p monitors in a grid) especially with higher numbers of monitors, global coordinates could be quite useful. For example in a 4 monitor grid setup (2x2) if a user typically had up to 4 windows in a grid (2x2) on each screen, then the user could use some modifier keys (e.g. W-C) with the keys in the 4x4 grid of 1-4, q-r, a-f, z-v and quickly switch between windows.

[brainwater]

Have you had a chance to review these changes?