[librsvg] Link to the generated internals docs

[Federico Mena Quintero <federico src gnome org>]

commit da712ab8cb16d2e2cb9af05aceac48779b816744
Author: Federico Mena Quintero <federico gnome org>
Date:   Wed Nov 13 14:18:26 2019 -0600

    Link to the generated internals docs

 ARCHITECTURE.md | 3 +++
 CONTRIBUTING.md | 3 +++
 2 files changed, 6 insertions(+)
---
diff --git a/ARCHITECTURE.md b/ARCHITECTURE.md
index 1898398b..291e8b55 100644
--- a/ARCHITECTURE.md
+++ b/ARCHITECTURE.md
@@ -4,6 +4,9 @@ Architecture of librsvg
 This document describes the architecture of librsvg, and future plans
 for it.
 
+The library's internals are being documented at
+https://gnome.pages.gitlab.gnome.org/librsvg/doc/rsvg_internals/index.html
+
 # A bit of history
 
 Librsvg is an old library.  It started around 2001, when Eazel (the
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index d54a99a2..a9502e8b 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -82,6 +82,9 @@ with a sample SVG file.
 
 ## Hacking on librsvg
 
+The library's internals are being documented at
+https://gnome.pages.gitlab.gnome.org/librsvg/doc/rsvg_internals/index.html
+
 ### Working on the source
 
 Librsvg uses an autotools setup, which is described in detail [in this