Url: introduce global helper functions for cleanup and scheme detection

Relates to #314 & #326

Additions:
 - add global `cleanup_url()` and `get_url_scheme()` functions

Modifications:
 - replace `Url` usage in `index.php` by calls to global functions
 - fix `Url` tests not being run: PHPUnit expects a single test class per file
   - move classes to separate files

2 files changed, 32 insertions, 2 deletions

diff --git a/application/LinkDB.php b/application/LinkDB.php
index 463aa47e..84733505 100644
--- a/application/LinkDB.php
+++ b/application/LinkDB.php
@@ -287,6 +287,10 @@ You use the community supported version of the original Shaarli project, by Seba
 
     /**
      * Returns the link for a given URL, or False if it does not exist.
+     *
+     * @param string $url URL to search for
+     *
+     * @return mixed the existing link if it exists, else 'false'
      */
     public function getLinkFromUrl($url)
     {
diff --git a/application/Url.php b/application/Url.php
index 02a4395d..af43b457 100755
--- a/application/Url.php
+++ b/application/Url.php
@@ -26,6 +26,32 @@ function unparse_url($parsedUrl)
 }
 
 /**
+ * Removes undesired query parameters and fragments
+ *
+ * @param string url Url to be cleaned
+ *
+ * @return string the string representation of this URL after cleanup
+ */
+function cleanup_url($url)
+{
+  $obj_url = new Url($url);
+  return $obj_url->cleanup();
+}
+
+/**
+ * Get URL scheme.
+ *
+ * @param string url Url for which the scheme is requested
+ *
+ * @return mixed the URL scheme or false if none is provided.
+ */
+function get_url_scheme($url)
+{
+  $obj_url = new Url($url);
+  return $obj_url->getScheme();
+}
+
+/**
  * URL representation and cleanup utilities
  *
  * Form
@@ -90,7 +116,7 @@ class Url
     /**
      * Returns a string representation of this URL
      */
-    public function __toString()
+    public function toString()
     {
         return unparse_url($this->parts);
     }
@@ -149,7 +175,7 @@ class Url
     {
         $this->cleanupQuery();
         $this->cleanupFragment();
-        return $this->__toString();
+        return $this->toString();
     }
 
     /**