Update mysql-otp dep version

Makefile

@@ -1,5 +1,5 @@
 PROJECT = mysql_poolboy
 DEPS = mysql poolboy
-dep_mysql = git https://github.com/mysql-otp/mysql-otp.git 1.1.1
+dep_mysql = git https://github.com/mysql-otp/mysql-otp.git 1.2.0
 dep_poolboy = git https://github.com/devinus/poolboy.git 1.5.1
 include erlang.mk