fix BufferedInputStream.read regression
fix BufferedInputStream.read regression

In commit 7fffba2, I had modified BufferedInputStream.read to keep
reading until in.available() <= 0 or an EOF was reached, but neglected
to update the offset into the destination buffer after each read.
This caused the previously-read data to be overwritten.  This commit
fixes that regression.

ucdseniordesign/avian,badlogic/avian,lwahlmeier/avian,marcinolawski/avian,marcinolawski/avian,lwahlmeier/avian,getlantern/avian,badlogic/avian,joshuawarner32/avian,dicej/avian,lostdj/avian,lwahlmeier/avian,bgould/avian,dicej/avian,MaartenR/avian,ucdseniordesign/avian,marcinolawski/avian,bgould/avian,lwahlmeier/avian,lostdj/avian,marcinolawski/avian,minor-jason/avian,dicej/avian,bgould/avian,getlantern/avian,joshuawarner32/avian,badlogic/avian,dicej/avian,lostdj/avian,minor-jason/avian,minor-jason/avian,getlantern/avian,bgould/avian,ucdseniordesign/avian,MaartenR/avian,bigfatbrowncat/avian-pack.avian,bigfatbrowncat/avian-pack.avian,getlantern/avian,ucdseniordesign/avian,bigfatbrowncat/avian-pack.avian,bigfatbrowncat/avian-pack.avian,lostdj/avian,minor-jason/avian,badlogic/avian,MaartenR/avian,joshuawarner32/avian,MaartenR/avian,joshuawarner32/avian