Image optimizations and corrections

* Optimized spinner gif
* WAY REDUCED tab-icon.jpg... even at 100% quality it's still smaller than the original :\
* Created alternate larger sizes for favicon
* Corrected favicon.ico to actually be an icon data type instead of png
* File permission corrections for exec bit on a few of these :\
Merge pull request #124 from Martii/imageOpts

Image optimizations and corrections