Fixes markdown sytax errors

src/ruby/README.md

@@ -14,9 +14,10 @@ INSTALLING
 ----------
 
 - Install the gRPC core library
-TODO: describe this, once the core distribution mechanism is defined.
-
+  TODO: describe this, once the core distribution mechanism is defined.
+```
 $ gem install grpc
+```
 
 
 Installing from source
@@ -24,37 +25,47 @@ Installing from source
 
 - Build or Install the gRPC core
 E.g, from the root of the grpc [git repo](https://github.com/google/grpc)
+```
 $ cd ../..
 $ make && sudo make install
+```
 
 - Install Ruby 2.x. Consider doing this with [RVM](http://rvm.io), it's a nice way of controlling
   the exact ruby version that's used.
+```
 $ command curl -sSL https://rvm.io/mpapis.asc | gpg --import -
 $ \curl -sSL https://get.rvm.io | bash -s stable --ruby
 $
 $ # follow the instructions to ensure that your're using the latest stable version of Ruby
 $ # and that the rvm command is installed
+```
 
 - Install [bundler](http://bundler.io/)
+```
 $ gem install bundler
+```
 
 - Finally, install grpc ruby locally.
+```
 $ cd <install_dir>
 $ bundle install
 $ rake  # compiles the extension, runs the unit tests, see rake -T for other options
-
+```
 
 CONTENTS
 --------
 
 Directory structure is the layout for [ruby extensions](http://guides.rubygems.org/gems-with-extensions/)
 
- * ext: the extension code
- * lib: the entrypoint grpc ruby library to be used in a 'require' statement
- * spec: tests
- * bin: example gRPC clients and servers, e.g,
+- ext:
+  the gRPC ruby extension
+- lib:
+  the entrypoint grpc ruby library to be used in a 'require' statement
+- spec:
+  Rspec unittest
+- bin:
+  example gRPC clients and servers, e.g,
 ```ruby
-# client
 stub = Math::Math::Stub.new('my.test.math.server.com:8080')
 req = Math::DivArgs.new(dividend: 7, divisor: 3)
 logger.info("div(7/3): req=#{req.inspect}")