Add robots.txt for web robots

Allow all robots to access any part of the site. This may change in the
future, as the html snippets that are generated for the posts and pages
should not be directly indexed.

See: http://www.robotstxt.org/robotstxt.html

Signed-off-by: Collin J. Doering <collin.doering@rekahsoft.ca>

robots.txt

@@ -0,0 +1,2 @@
+User-agent: *
+Allow: /

src/site.hs

@@ -105,7 +105,7 @@ main = do
 
   hakyllWith myConfig $ do
 -- All Versions ------------------------------------------------------------------------------------------
-    match ("action/**" .||. "files/**" .||. "images/**" .||. "fonts/**") $ do
+    match ("action/**" .||. "files/**" .||. "images/**" .||. "fonts/**" .||. "robots.txt") $ do
       route   idRoute
       compile copyFileCompiler