Use tagged versions in deps

rebar.config

@@ -1,4 +1,4 @@
 {deps, [
-    {mysql, ".*", {git, "https://github.com/mysql-otp/mysql-otp.git", {branch, "master"}}},
-    {poolboy, ".*", {git, "https://github.com/devinus/poolboy.git", {branch, "master"}}}
+    {mysql, ".*", {git, "https://github.com/mysql-otp/mysql-otp.git", {tag, "0.8.0"}}},
+    {poolboy, ".*", {git, "https://github.com/devinus/poolboy.git", {tag, "1.4.2"}}}
 ]}.