Retrieve Add values for high-bit blocks.
Fix infinite loop while writing a chunk changing the way in which free space is searched in the region file.
Add exception when opening files too small to be a region file.
Merge pull request #66 from Fenixin/fix-update

Fix infinite loop when writing a chunk. Add new exception.
Fixed a bug that sometimes made write chunks in the region file header.

parse_header() now updates the file size before parsing the header
making possible to call it after modifiying the region file.

Now the header is updated everytime the region file is modified.
Merge pull request #67 from Fenixin/fix

Fixed a bug that sometimes made write chunks in the region file header.
Merge branch 'master' of https://github.com/twoolie/NBT

merge origin.