Merge mozjpeg into libjpeg-turbo

* origin/master: (23 commits)
  Update .gitignore
  .func/.endfunc are only necessary when generating STABS debug info, which basically went out of style with parachute pants and Rick Astley.  At any rate, none of the platforms for which we're building the ARM code use it (DWARF is the common format these days), and the .func/.endfunc directives cause the clang integrated assembler to fail (http://llvm.org/bugs/show_bug.cgi?id=20424).
  Enable DC trellis by default
  Avoid double inline attribute
  Detect libpng
  Implement DHT Merging
  Add .gitignore for autotools files
  Check memory alloc success
  Update cjpeg usage text
  Implement DQT merging
  Fix issue with scan printout
  Get rid of unnecessary and obsolete platform configuration instructions.
  Add error checks for malloc calls that don't already have them. Issue #87.
  yuvjpeg: fix trivial leak
  Parse quality as float
  PNG reading support
  Fix issue with DC trellis
  Add option to split DC scans
  Add trellis for DC
  Bump version to 2.1.
  ...

Conflicts:
	BUILDING.txt
	cdjpeg.h
	jcdctmgr.c
	jchuff.h
	jcmarker.c
	jcmaster.c
	jconfig.txt
	jpeglib.h
	rdswitch.c

jchuff.h

@@ -29,8 +29,8 @@
 /* Derived data constructed for each Huffman table */
 
 typedef struct {
-  unsigned int ehufco[256];     /* code for each symbol */
-  char ehufsi[256];             /* length of code for each symbol */
+  unsigned int ehufco[256];	/* code for each symbol */
+  char ehufsi[256];		/* length of code for each symbol */
   /* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */
 } c_derived_tbl;
 
@@ -44,5 +44,5 @@ EXTERN(void) jpeg_gen_optimal_table
         (j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[]);
 
 EXTERN(void) quantize_trellis
-        (j_compress_ptr cinfo, c_derived_tbl *actbl, JBLOCKROW coef_blocks, JBLOCKROW src, JDIMENSION num_blocks,
-                 JQUANT_TBL * qtbl, double *norm_src, double *norm_coef);
+        (j_compress_ptr cinfo, c_derived_tbl *dctbl, c_derived_tbl *actbl, JBLOCKROW coef_blocks, JBLOCKROW src, JDIMENSION num_blocks,
+                 JQUANT_TBL * qtbl, double *norm_src, double *norm_coef, JCOEF *last_dc_val);