Added documentation for net_http gem in instrumentation

instrumentation/net_http/README.md

@@ -0,0 +1,53 @@
+# OpenTelemetry Net::HTTP Instrumentation
+
+The OpenTelemetry Net::HTTP Ruby gem is a community maintained instrumentation for [Net::HTTP][net-http-home]. 
+
+## How do I get started?
+
+Install the gem using:
+
+```
+gem install opentelemetry-instrumentation-net_http
+```
+
+Or, if you use [bundler][bundler-home], include `opentelemetry-instrumentation-net_http` in your `Gemfile`.
+
+## Usage
+
+To install the instrumentation, call `use` with the name of the instrumentation.
+
+```ruby
+OpenTelemetry::SDK.configure do |c|
+  c.use 'OpenTelemetry::Instrumentation::Net::HTTP'
+end
+```
+
+Alternatively, you can also call `use_all` to install all the available instrumentation.
+
+```ruby
+OpenTelemetry::SDK.configure do |c|
+  c.use_all
+end
+```
+
+## Example
+
+An example of usage can be seen in [`example/net_http.rb`](https://github.com/open-telemetry/opentelemetry-ruby/blob/master/instrumentation/net_http/example/net_http.rb).
+
+## How can I get involved?
+
+The `opentelemetry-instrumentation-net_http` gem source is [on github][repo-github], along with related gems including `opentelemetry-api` and `opentelemetry-sdk`.
+
+The OpenTelemetry Ruby gems are maintained by the OpenTelemetry-Ruby special interest group (SIG). You can get involved by joining us on our [gitter channel][ruby-gitter] or attending our weekly meeting. See the [meeting calendar][community-meetings] for dates and times. For more information on this and other language SIGs, see the OpenTelemetry [community page][ruby-sig].
+
+## License
+
+Apache 2.0 license. See [LICENSE][license-github] for more information.
+
+[net-http-home]: https://docs.ruby-lang.org/en/2.0.0/Net/HTTP.html
+[bundler-home]: https://bundler.io
+[repo-github]: https://github.com/open-telemetry/opentelemetry-ruby
+[license-github]: https://github.com/open-telemetry/opentelemetry-ruby/blob/master/LICENSE
+[ruby-sig]: https://github.com/open-telemetry/community#ruby-sig
+[community-meetings]: https://github.com/open-telemetry/community#community-meetings
+[ruby-gitter]: https://gitter.im/open-telemetry/opentelemetry-ruby