Added 'dist' target to Makefile that does a sanity check on tarball.

Makefile

@@ -1,3 +1,4 @@
+version=$(shell grep '^Version:' pandoc.cabal | awk '{print $$2;}')
 makemanpages=$(shell find dist -type f -name make-pandoc-man-pages)
 ifeq "${makemanpages}" ""
 	makemanpages=@echo "You need to 'cabal configure -fmake-pandoc-man-pages && cabal build'" && exit 1
@@ -27,10 +28,17 @@ install:
 haddock:
 	cabal haddock
 
-sdist: build test man haddock
+sdist: man haddock
 	# note: cabal sdist doesn't work well with preprocessors for some cabal versions
 	${setup} sdist
 
+# sanity check on sdist
+dist: sdist
+	rm -rf "pandoc-${version}"
+	tar xvzf dist/pandoc-${version}.tar.gz
+	cd pandoc-${version}
+	cabal configure ${CABALARGS} && cabal build && cabal test && cd .. && rm -rf "pandoc-${version}"
+
 man: ${MANPAGES}
 
 %.1: %.1.template