fixed las and laz output
updated README
Merge pull request #64 from potree/develop

Develop
We use the ptx transformation header, if found in the LAS file.
Merge pull request #66 from Antea/ptx_vlr

Ptx vlr
fixed variable initialization
added classification, point source and return number
Update README.md
Merge pull request #68 from potree/develop

Develop
Merge remote-tracking branch 'upstream/master'