Fix for pasp atom box - Githubissues

What steps will reproduce the problem?
1. Open a mp4 file generates on some modern smartphone with 
PixelAspectRationAtom box (pasp) in the avc1 box.
2. Isoviewer 0.28 fails to parse the pasp box. Rebuilding the movie with 
isoparser, the resulting pasp box is not correct.

What is the expected output? What do you see instead?
I expect to see the atom details in the gui and to rebuild correctly the mp4 
file.

What version of the product are you using? On what operating system?
0.28 on mac and android.

Please provide any additional information below.
According to QuickTime File Format Specification 
https://developer.apple.com/library/mac/documentation/quicktime/qtff/QTFFChap3/q
tff3.html#//apple_ref/doc/uid/TP40000939-CH205-124550 (find for "pasp"),
the "version" and the "flags" fields should not be present.

It's enough to remove the lines parseVersionAndFlags(content); and 
writeVersionAndFlags(byteBuffer); to fix the issue.

Original issue reported on code.google.com by gluca.mo...@gmail.com on 14 Jan 2014 at 1:34

mmlii / mp4parser

Fix for pasp atom box #80