files that end with .nw

[Olorin]

The format that the *.nw levels are in is the GLEVNW01 format. I asked Stefan to use it when developing G2K1 last December, and it kinda stuck... it was only supposed to be used because of some of the ideas we had... that of course never were developed. It uses a text format that has a 12bit index and is encoded in a base64 format so AA is tile 0, AB is tile one.... and so on and so forth...