Reorganize makefile a bit

Makefile.am

@@ -1,17 +1,25 @@
 ACLOCAL_AMFLAGS = -I m4
+AM_CXXFLAGS = $(CUPS_CFLAGS)
+TESTS = $(check_PROGRAMS)
 
-dist_doc_DATA = README.md
 
-filter_PROGRAMS = rastertobrlaser
-filterdir = $(CUPS_SERVERBIN)/filter
+dist_doc_DATA = README.md
 
 drv_DATA = brlaser.drv
 drvdir = $(CUPS_DATADIR)/drv
 
-noinst_PROGRAMS = brdecode
+filter_PROGRAMS = src/rastertobrlaser
+filterdir = $(CUPS_SERVERBIN)/filter
+
+noinst_PROGRAMS = src/brdecode
 
+check_PROGRAMS = \
+	test/test_lest \
+	test/test_line \
+	test/test_block
 
-rastertobrlaser_SOURCES = \
+
+src_rastertobrlaser_SOURCES = \
 	src/main.cc \
 	src/debug.h \
 	src/debug.cc \
@@ -20,24 +28,22 @@ rastertobrlaser_SOURCES = \
 	src/block.h \
 	src/line.h \
 	src/line.cc
-rastertobrlaser_CPPFLAGS = $(CUPS_CFLAGS)
-rastertobrlaser_LDADD = $(CUPS_LIBS)
+src_rastertobrlaser_LDADD = $(CUPS_LIBS)
 
-brdecode_SOURCES = \
+src_brdecode_SOURCES = \
 	src/brdecode.cc
 
-
-TESTS = test_lest test_line test_block
-check_PROGRAMS = $(TESTS)
-test_lest_SOURCES = \
+test_test_lest_SOURCES = \
 	test/test_lest.cc \
 	test/lest.h
-test_line_SOURCES = \
+
+test_test_line_SOURCES = \
 	test/test_line.cc \
 	src/line.h \
 	src/line.cc \
 	test/lest.h
-test_block_SOURCES = \
+
+test_test_block_SOURCES = \
 	test/test_block.cc \
 	src/block.h \
 	test/tempfile.h \