Update Makefile (#64)

diff --git a/Makefile b/Makefile
index 4264698..697fda5 100644
--- a/Makefile
+++ b/Makefile
@@ -37,13 +37,14 @@
 .PHONY: release-src
 release-src:
 	tar -zcvf $(RELEASE_SRC).tgz \
-	--exclude bin \
-	--exclude .git \
-	--exclude .idea \
-	--exclude .gitignore \
-	--exclude .DS_Store \
-	--exclude .github \
-	.
+		./examples \
+		./licenses \
+		./rockspec \
+		./lib \
+		./t \
+		./Makefile \
+		./NOTICE \
+		./*.md 
 
 	gpg --batch --yes --armor --detach-sig $(RELEASE_SRC).tgz
 	shasum -a 512 $(RELEASE_SRC).tgz > $(RELEASE_SRC).tgz.sha512
@@ -52,3 +53,4 @@
 	mv $(RELEASE_SRC).tgz release/$(RELEASE_SRC).tgz
 	mv $(RELEASE_SRC).tgz.asc release/$(RELEASE_SRC).tgz.asc
 	mv $(RELEASE_SRC).tgz.sha512 release/$(RELEASE_SRC).tgz.sha512
+