Delete Step_1.md

Remove separate step now that all the content has been moved into the main doc

Step_1.md

-# Step-1: Generate a service client.
-
-In this step, we use protoc to generate the Java Stub classes.  A Stub is the
-name gRPC uses for the code that initiates contact with a gRPC service running
-remotely via the internet.
-
-If you did not install protoc on your system, you can skip this step and move
-onto the next one where we examine the generated code.
-
-First, you'll need to build the protobuf plugin that generates the rpc
-classes.  `protoc` uses other tools called plugins to add additional features
-to generated code.
-
-The gRPC Java Stub classes are created using a gRPC Java plugin, but first the
-plugin must be built and installed.
-
-To build the plugin:
-```
-$ pushd external/grpc_java
-$ make java_plugin
-$ popd
-```
-
-To use it to generate the code:
-```
-$ mkdir -p src/main/java
-$ protoc -I . helloworld.proto --plugin=protoc-gen-grpc=external/grpc_java/bins/opt/java_plugin \
-                               --grpc_out=src/main/java \
-                               --java_out=src/main/java
-```
-
-Next, in [Step - 2](Step_2.md), we'll use the generated Stub implementation to
-write a client that uses the generated code to make a call to a service.