posix tar does not handle long filenames

[jendap]

Standard posix tar files have long filenames in extended headers (header "path=/some/very/long/filename").

The header is simply skipped now - see "Skip over pax extended header and global extended header records." in tar.c

Steps to reproduce the tar file:
echo "foo" >very_0_very_1_very_2_very_3_very_4_very_5_very_6_very_7_very_8_very_9_very_10_very_11_very_12_long_filename
tar cf foo.tar --format=posix very*

BTW: This is important especially in java world as there are deep directories and long filenames - virtually no tar file of any java project can be opened correctly in mc.

[andrew_b]

Duplicate of #2201.