Include magnum-extras repo in Doxygen documentation.

Doxyfile

@@ -154,7 +154,8 @@ FULL_PATH_NAMES        = YES
 
 STRIP_FROM_PATH        = ../magnum/src \
                          ../magnum-plugins/src \
-                         ../magnum-integration/src
+                         ../magnum-integration/src \
+                         ../magnum-extras/src
 
 # The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of the
 # path mentioned in the documentation of a class, which tells the reader which
@@ -165,7 +166,8 @@ STRIP_FROM_PATH        = ../magnum/src \
 
 STRIP_FROM_INC_PATH    = ../magnum/src \
                          ../magnum-plugins/src \
-                         ../magnum-integration/src
+                         ../magnum-integration/src \
+                         ../magnum-extras/src
 
 # If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter (but
 # less readable) file names. This can be useful is your file systems doesn't
@@ -810,7 +812,9 @@ INPUT                  = src/Magnum \
                          ../magnum-plugins/doc/ \
                          ../magnum-integration/src/Magnum \
                          ../magnum-integration/doc/ \
-                         ../magnum-examples/doc/
+                         ../magnum-examples/doc/ \
+                         ../magnum-extras/src/Magnum \
+                         ../magnum-extras/doc/ \
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses

doc/getting-started.dox

@@ -224,9 +224,11 @@ experimenting on your own!
 -   @subpage building-plugins
 -   @subpage building-integration
 -   @subpage building-examples
+-   @subpage building-extras
 -   @subpage cmake
 -   @subpage cmake-plugins
 -   @subpage cmake-integration
+-   @subpage cmake-extras
 
 */
 }