[Go] Working on a go example plus fixing go grpc code (#6448)

Implemented server.go and half implemented client.go

Finishes implementation for greeter go example

Update grpc code for monster.fbs

Adds a couple of cpp methods

Adhere to gofmt standards

Adds a readme for issues with grpc

grpc/examples/generate.sh

@@ -0,0 +1,18 @@
+current_dir=`pwd`
+
+cd ../..
+
+main_dir=`pwd`
+
+cd ${current_dir}
+
+alias fbc='${main_dir}/Debug/flatc'
+generator="--grpc $current_dir/greeter.fbs"
+
+# Regenerate Go lang code
+cd go/
+
+cd greeter
+fbc --go ${generator}
+
+cd ../..