Fix links in README.md and overview.edoc (#175)

* Fix links

* Fix link to repository

README.md

@@ -131,7 +131,7 @@ Where to go from here
 ---------------------
 
 To get started on using PropEr, see the tutorials and testing tips provided on
-[PropEr's home page](http://proper.softlab.ntua.gr). On the same site you can
+[PropEr's home page](http://proper-testing.github.io). On the same site you can
 find a copy of PropEr's API documentation (you can also build this from source
 if you prefer, by running `make doc`), as well as links to more resources on
 property-based testing.

doc/overview.edoc

@@ -28,7 +28,7 @@ This is the source for PropEr's overview page.
 
 @doc This is PropEr's Reference Manual. If you are new to PropEr, you should
 first read the User Guide (available online at
-<a href="http://proper.softlab.ntua.gr/" target="_top">PropEr's website</a>,
+<a href="http://proper-testing.github.io" target="_top">PropEr's website</a>,
 and also in PropEr's README file). The bulk of the PropEr API is contained in
 the documentation for the following modules:
 

mix.exs

@@ -25,6 +25,6 @@ defmodule Proper.Mixfile do
      [files: ~w(src include rebar.config configure Makefile COPYING README.md THANKS check_escripts.sh clean_doc.sh clean_temp.sh mix.exs),
      maintainers: ["Manolis Papadakis", "Eirini Arvaniti", "Kostis Sagonas"],
      licenses: ["GPL"],
-     links: %{"GitHub" => "https://github.com/manopapad/proper"}]
+     links: %{"GitHub" => "https://github.com/proper-testing/proper"}]
    end
 end