Build: Include 04_compress_easy_mt.c in the tarball.
diff --git a/Makefile.am b/Makefile.am
index dcfcc89..1053697 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -37,6 +37,7 @@
 	doc/examples/01_compress_easy.c \
 	doc/examples/02_decompress.c \
 	doc/examples/03_compress_custom.c \
+	doc/examples/04_compress_easy_mt.c \
 	doc/examples/Makefile
 
 examplesolddir = $(docdir)/examples_old