Bump github.com/golang/protobuf from 1.3.1 to 1.3.2

Bumps [github.com/golang/protobuf](https://github.com/golang/protobuf) from 1.3.1 to 1.3.2.
- [Release notes](https://github.com/golang/protobuf/releases)
- [Commits](golang/protobuf@v1.3.1...v1.3.2)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

go.mod

@@ -2,4 +2,4 @@ module github.com/vimeda/pletter
 
 go 1.12
 
-require github.com/golang/protobuf v1.3.1
+require github.com/golang/protobuf v1.3.2

go.sum

@@ -1,2 +1,4 @@
 github.com/golang/protobuf v1.3.1 h1:YF8+flBXS5eO826T4nzqPrxfhQThhXl0YzfuUPu4SBg=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
+github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=