Use zend-{package}, not Zend\\{Namespace}

Additionally, most cases of `Zend\Expressive` were changed to simply
`Expressive`.

Also updated the link to the skeleton installer.

Author: weierophinney

doc/book/why-expressive.md

@@ -1,30 +1,30 @@
-# Should You Choose Zend\Expressive Over Zend\Mvc?
+# Should You Choose zend-expressive Over zend-mvc?
 
-After creating several projects with Zend\Expressive, we recommend that you
+After creating several projects with zend-expressive, we recommend that you
 choose Expressive for any new project — _if the choice is yours to make_.
 
-## We Recommend Zend\Expressive
+## We Recommend Expressive
 
-[Zend\MVC](https://github.com/zendframework/zend-mvc) has many preconceptions
+[zend-mvc](https://github.com/zendframework/zend-mvc) has many preconceptions
 about how things work, yet they're very broad and unspecific.  What’s more, it
 also has several pre-wired structures in place.
 
 As a result, you are required to know a lot of what those things are — *if* you
 want to use it optimally.  And to acquire that depth of knowledge, you’re going
-to need to spend a lot of time, digging deep into Zend\Mvc’s internals, before
+to need to spend a lot of time, digging deep into zend-mvc’s internals, before
 you begin to get the most out of it.
 
 To quote Zend Framework project lead, [Matthew Weier O’Phinney](https://twitter.com/mwop):
 
-> The problem is that Zend\Mvc is anything but beginner-friendly at this point.
+> The problem is that zend-mvc is anything but beginner-friendly at this point.
 > You're required to deep dive into the event manager, service manager, and
 > module system — right from the outset; And to do this you need more than a
 > passing understanding of object-oriented programming and a range of design
 > patterns.
 
-Zend\Expressive (specifically applications based on [the Expressive Skeleton
-Installer](https://zendframework.github.io/zend-expressive/)) on the other hand,
-comes with barely any of these assumptions and requirements.
+Expressive (specifically applications based on
+[the Expressive Skeleton Installer](https://docs.zendframework.com/zend-expressive/getting-started/skeleton/))
+on the other hand, comes with barely any of these assumptions and requirements.
 
 It provides a very minimalist structure. Essentially all you have to become
 familiar with are five core components. These are:
@@ -37,25 +37,25 @@ familiar with are five core components. These are:
 
 Given that, you can quickly get up to speed with the framework and begin
 creating the application that you need.  We believe that this approach — in
-contrast to the Zend\Mvc approach — is more flexible and accommodating.
+contrast to the zend-mvc approach — is more flexible and accommodating.
 
 What’s more, you can mix and match the types of applications that you create.
 
 - Do you just need an API? Great; you can do that quite quickly.
 - Do you want an HTML-based front-end? That’s available too.
 
-When building applications with Zend\Expressive, you can make use of any other
+When building applications with Expressive, you can make use of any other
 Zend library, or non-Zend library.  You can pick and choose what you need, as
 and when you need it.  You’re not bound by many, if any, constraints and design
 decisions.
 
 ## In Conclusion
 
-For what it’s worth, we’re **not** saying that Zend\Mvc is a poor choice!  What
+For what it’s worth, we’re **not** saying that zend-mvc is a poor choice!  What
 we are saying is:
 
 1. The learning curve, from getting started to building the first application,
-   is _significantly_ lower with Zend\Expressive
+   is _significantly_ lower with Expressive
 2. The ways in which you can create applications, whether through multiple
    pieces of middleware or by combining multiple Expressive apps, into one
    larger one, is a much more efficient and fluid way to work