Add mgv5

![screenshot_1399045933](https://cloud.githubusercontent.com/assets/3686677/4963824/494cd22e-6730-11e4-92b8-7b538b3e9282.png)


The generation of dirt/sand/gravel/lava blobs is intended to be optional using a 'blobs' spflag. When tested the game ran, the blobs flag appeared in map meta txt, but all blobs failed to appear. Removing the if statement from around generateBlobs() in makeChunk somehow solves the problem, so i have commented out my spflag code and made blobs temporarily compulsory.