Fixing import for airbrake and adding build constraint to example hook

diff --git a/README.md b/README.md
index f8302c3..8ce5db9 100644
--- a/README.md
+++ b/README.md

@@ -1,4 +1,4 @@
-# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/>&nbsp;[![Build Status](https://travis-ci.org/Sirupsen/logrus.svg?branch=master)](https://travis-ci.org/Sirupsen/logrus)&nbsp;[![GoDoc](https://godoc.org/github.com/Sirupsen/logrus?status.svg)](https://godoc.org/github.com/Sirupsen/logrus)
+# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/>&nbsp;[![Build Status](https://travis-ci.org/sirupsen/logrus.svg?branch=master)](https://travis-ci.org/sirupsen/logrus)&nbsp;[![GoDoc](https://godoc.org/github.com/sirupsen/logrus?status.svg)](https://godoc.org/github.com/sirupsen/logrus)
 
 Logrus is a structured logger for Go (golang), completely API compatible with
 the standard library logger. [Godoc][godoc]. **Please note the Logrus API is not
@@ -54,7 +54,7 @@
 package main
 
 import (
-  log "github.com/Sirupsen/logrus"
+  log "github.com/sirupsen/logrus"
 )
 
 func main() {
@@ -65,7 +65,7 @@
 ```
 
 Note that it's completely api-compatible with the stdlib logger, so you can
-replace your `log` imports everywhere with `log "github.com/Sirupsen/logrus"`
+replace your `log` imports everywhere with `log "github.com/sirupsen/logrus"`
 and you'll now have the flexibility of Logrus. You can customize it all you
 want:
 
@@ -74,7 +74,7 @@
 
 import (
   "os"
-  log "github.com/Sirupsen/logrus"
+  log "github.com/sirupsen/logrus"
 )
 
 func init() {
@@ -123,7 +123,7 @@
 package main
 
 import (
-  "github.com/Sirupsen/logrus"
+  "github.com/sirupsen/logrus"
 )
 
 // Create a new instance of the logger. You can have any number of instances.
@@ -176,9 +176,9 @@
 
 ```go
 import (
-  log "github.com/Sirupsen/logrus"
+  log "github.com/sirupsen/logrus"
   "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "aibrake"
-  logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog"
+  logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
   "log/syslog"
 )
 
@@ -203,7 +203,7 @@
 | [Airbrake](https://github.com/gemnasium/logrus-airbrake-hook) | Send errors to the Airbrake API V3. Uses the official [`gobrake`](https://github.com/airbrake/gobrake) behind the scenes. |
 | [Airbrake "legacy"](https://github.com/gemnasium/logrus-airbrake-legacy-hook) | Send errors to an exception tracking service compatible with the Airbrake API V2. Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. |
 | [Papertrail](https://github.com/polds/logrus-papertrail-hook) | Send errors to the [Papertrail](https://papertrailapp.com) hosted logging service via UDP. |
-| [Syslog](https://github.com/Sirupsen/logrus/blob/master/hooks/syslog/syslog.go) | Send errors to remote syslog server. Uses standard library `log/syslog` behind the scenes. |
+| [Syslog](https://github.com/sirupsen/logrus/blob/master/hooks/syslog/syslog.go) | Send errors to remote syslog server. Uses standard library `log/syslog` behind the scenes. |
 | [Bugsnag](https://github.com/Shopify/logrus-bugsnag/blob/master/bugsnag.go) | Send errors to the Bugsnag exception tracking service. |
 | [Sentry](https://github.com/evalphobia/logrus_sentry) | Send errors to the Sentry error logging and aggregation service. |
 | [Hiprus](https://github.com/nubo/hiprus) | Send errors to a channel in hipchat. |
@@ -277,7 +277,7 @@
 
 ```go
 import (
-  log "github.com/Sirupsen/logrus"
+  log "github.com/sirupsen/logrus"
 )
 
 init() {

diff --git a/alt_exit_test.go b/alt_exit_test.go
index 022b778..d182963 100644
--- a/alt_exit_test.go
+++ b/alt_exit_test.go

@@ -44,7 +44,7 @@
 package main
 
 import (
-	"github.com/Sirupsen/logrus"
+	"github.com/sirupsen/logrus"
 	"flag"
 	"fmt"
 	"io/ioutil"

diff --git a/examples/hook/hook.go b/examples/hook/hook.go
index 04e08f4..91b41ee 100644
--- a/examples/hook/hook.go
+++ b/examples/hook/hook.go

@@ -1,3 +1,9 @@
+// +build ignore
+// Do NOT include the above line in your code. This is a build contrainst used
+// to prevent import loops in the code whilst go get'ting it.
+// Read more about build contrains in golang here:
+// https://golang.org/pkg/go/build/#hdr-Build_Constraints
+
 package main
 
 import (

diff --git a/hooks/syslog/README.md b/hooks/syslog/README.md
index 066704b..92b391c 100644
--- a/hooks/syslog/README.md
+++ b/hooks/syslog/README.md

@@ -5,8 +5,8 @@
 ```go
 import (
   "log/syslog"
-  "github.com/Sirupsen/logrus"
-  logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog"
+  "github.com/sirupsen/logrus"
+  logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
 )
 
 func main() {
@@ -24,8 +24,8 @@
 ```go
 import (
   "log/syslog"
-  "github.com/Sirupsen/logrus"
-  logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog"
+  "github.com/sirupsen/logrus"
+  logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
 )
 
 func main() {
@@ -36,4 +36,4 @@
     log.Hooks.Add(hook)
   }
 }
-```
\ No newline at end of file
+```