Added self-updating, better docker-compose control

* Added --self-update to check for and download new versions of
  the phar
* Added --only option which accepts a comma-separated list of
  services to pass to docker-compose pull/up
* Added --updated option to only pass the updated services to
  docker-compose pull/up

src/Configuration/ComposeConfiguration.php

@@ -9,6 +9,8 @@ class ComposeConfiguration
 
     private array $checks = [];
 
+    private array $services = [];
+
     public function __construct(string $configfile)
     {
         $this->loadComposeFile($configfile);
@@ -23,6 +25,10 @@ class ComposeConfiguration
             if ($image && !in_array($image,$this->checks)) {
                 $this->checks[] = $image;
             }
+            if (!array_key_exists($image, $this->services)) {
+                $this->services[$image] = [];
+            }
+            $this->services[$image][] = $name;
         }
     }
 
@@ -30,4 +36,16 @@ class ComposeConfiguration
     {
         return $this->checks;
     }
+
+    public function getServicesForImages(array $images)
+    {
+        $ret = [];
+        foreach ($images as $ref) {
+            $image = (string)$ref->ref;
+            if (array_key_exists($image, $this->services)) {
+                $ret = array_merge($ret, $this->services[$image]);
+            }
+        }
+        return array_unique($ret);
+    }
 }