add -D_FILE_OFFSET_BITS=64 to fix 2gb file size limit

Fix 2gb file size limit by adding missing -D_FILE_OFFSET_BITS=64.
Previous pull request applied on 'next' branch instead of 'master'
Merge pull request #111 from SnowLeopard71/master

add -D_FILE_OFFSET_BITS=64 to fix 2gb file size limit