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

lib/gollum/page.rb

@@ -372,9 +372,9 @@ module Gollum
     # version - The String version ID to find.
     #
     # Returns a Gollum::Page or nil if the page could not be found.
-    def find(name, version, dir = nil)
+    def find(name, version, dir = nil, exact = false)
       map = @wiki.tree_map_for(version.to_s)
-      if page = find_page_in_tree(map, name, dir)
+      if page = find_page_in_tree(map, name, dir, exact)
         page.version    = version.is_a?(Grit::Commit) ?
           version : @wiki.commit_for(version)
         page.historical = page.version.to_s == version.to_s
@@ -391,12 +391,14 @@ module Gollum
     #               to be in.  The string should
     #
     # Returns a Gollum::Page or nil if the page could not be found.
-    def find_page_in_tree(map, name, checked_dir = nil)
+    def find_page_in_tree(map, name, checked_dir = nil, exact = false)
       return nil if !map || name.to_s.empty?
       if checked_dir = BlobEntry.normalize_dir(checked_dir)
         checked_dir.downcase!
       end
 
+      checked_dir = '' if exact && checked_dir.nil?
+
       map.each do |entry|
         next if entry.name.to_s.empty?
         next unless checked_dir.nil? || entry.dir.downcase == checked_dir