Fix #483 and #481

Exact matching of requested pages

- /page is no longer the same as /a/page
- Deleting /page only deletes /page (before it would delete /a/page instead of /page)
- Edit currently breaks the unit tests if exact matching is enabled
- Fix redirect on create
- Add @giga's checked_dir = '' fix https://github.com/giga/gollum/commit/936958b47324a09c683cb90a2560484b47e09529
- Fix create unit test

test/test_app.rb

@@ -176,7 +176,8 @@ context "Frontend" do
     name = "A"
     post "/create", :content => 'abc', :page => name,
       :format => 'markdown', :message => 'def'
-    assert last_response.ok?
+    # create redirects on success
+    assert_equal last_response.status, 302
 
     @wiki.clear_cache
     page = @wiki.page(name)