Higher DPI

**This should make mpc-hc more or less usable in higher dpi**

Things that didn't make into this PR (just for information, I don't plan to add anything to this one):
 - Some table controls default column widths don't scale up properly
 - All raster images should be replaced with vectors at some point (but we need an svg engine and quite a few decisions for that)
 - Per monitor dpi-awareness (http://msdn.microsoft.com/en-us/library/windows/desktop/dd464659%28v=vs.85%29.aspx)

**How it looks:**

![1](https://f.cloud.github.com/assets/2756009/1846578/aafebeea-7606-11e3-888e-d35581620503.png)
![2](https://f.cloud.github.com/assets/2756009/1846579/ab03c32c-7606-11e3-85aa-25991926e230.png)
![3](https://f.cloud.github.com/assets/2756009/1846580/ab084dde-7606-11e3-967f-d3e1f38daa0c.png)
![4](https://f.cloud.github.com/assets/2756009/1846581/ab0c7ab2-7606-11e3-95f2-866bef428ddb.png)