MJPEG Tools Svn

Error concealment patch submitted by Steve Tell (tell at telltronics dot org)

Since the default 'A' tag is square pixels it's more sensible to have the
default frame size be 640x480 (4:3 image).

Try to fix the problems with PPC + gcc4 + Fedora once and for all:
https://sourceforge.net/tracker/index.php?func=detail&aid=1215231&group_id=5776&atid=105776

Problem of undefined symbol (next_larger_quant) is caused by utils/altived/
libaltivec referencing encoder routines that are in libmpeg2encpp! Can't do
that because libmpeg2encpp hasn't been built yet!!

Attempted solution is to move mpeg2enc immediately after utils/ in the
top level Makefile.am. Then move mjpeg_simd_helper into lavtools/. THEN
add 'if HAVE_ALTIVEC' to all the other Makefile.am files and add libmpeg2encpp
to the list of library dependencies.

Klug? Sure - feel free to fix it differently :)

Hopefully the last of the pesky fedora gcc4 problems (wonder what RedHat did
to their gcc4 that Apple didn't?)

3 more "errors" that RedHat's gcc4 chokes on but Apple's does not.

Damed '{{{' style comments - hid a few more of the macros on the wrong side
of the assignment operator.

Typo fix (swapp -> swap) ;)

Library routines shouldn't log messages - they might be used when nothing should
appear. Let the caller print an error if desired.

Sigh -= the endian detectin logic was replicated in *3* places.
Consolidate into a common routine ("code reuse" is a Good Thing ;)).

Fix a couple spelling errors (lttle instead of little)