Improve javascript uglify handling

Auto detect javascript files.

debian/uglify/Makefile

@@ -3,9 +3,9 @@
 #
 # Fallback to yui-compressor if uglifyjs is not available.
 
-SOURCE_PATH = ../../public/js/vendor
-SOURCES = jquery-1.11.0.js jquery-2.1.0.js jquery.sparkline.js jquery.tipsy.js
-FILES = $(patsubst %.js,%.min.js,$(SOURCES))
+SOURCE_PATH := ../../public/js/vendor
+SOURCES := $(filter-out %.min.js,$(notdir $(wildcard $(SOURCE_PATH)/*.js)))
+MINIFIED := $(patsubst %.js,%.min.js,$(SOURCES))
 
 UGLIFY_OPTS = -m "toplevel=true" -r '$$,require,exports' -c "hoist_funs=false,loops=false,unused=false"
 
@@ -18,7 +18,7 @@ clean:
 
 source: $(SOURCES)
 
-uglify: $(FILES)
+uglify: $(MINIFIED)
 
 %.min.js: %.js
 	$(eval map := $(patsubst %.min.js,%.min.map,$@))