README: small updates after github migration

Make sure we have a small introduction in the README on github.

Signed-off-by: Brice Goglin <[email protected]>

README

@@ -1,8 +1,14 @@
+llgal is an easy and fast on-line gallery generator based on iGal.
+Its primary goal is to NOT require any boring useless expensive feature
+in your webserver, such as PHP, JavaScript, SQL, ...
+
+Thus, llgal generates static web-pages.
+
 llgal installation instructions
 ===============================
 
-You don't care about this if you use Debian or Gentoo prepackaged
-versions that are available on http://bgoglin.free.fr/llgal.
+You don't care about this if you use Debian or Gentoo or any other
+distribution that includes prepackaged lltag versions.
 
 Run 'make' followed by 'make install' as root.