Update SFML to version 2.2, remove sfml_git, and update MARS (depended on sfml_git)

pkgs/games/mars/unbind_fix.patch

@@ -0,0 +1,19 @@
+diff --git a/src/System/window.cpp b/src/System/window.cpp
+index e9a099a..e3f6de9 100644
+--- a/src/System/window.cpp
++++ b/src/System/window.cpp
+@@ -308,12 +308,12 @@ namespace window {
+         glEnable(GL_TEXTURE_2D);
+ 
+         if (shader)
+-            shader->bind();
++            sf::Shader::bind(shader);
+ 
+         window_.draw(toBeDrawn, states);
+ 
+         if (shader)
+-            shader->unbind();
++            sf::Shader::bind(NULL);
+ 
+         window_.popGLStates();
+         glPopMatrix();