[general][doc] Fixes in toolchains

doc/beat/toolchains.rst

@@ -69,8 +69,8 @@ fields:
         ]
     }
 
-Note that this toolchain is considered as a correct one by the platform (i.e.
-it doesn't contain any error, and thus can be modified via the web interface),
+Note that this toolchain is considered as a correct one by the system (i.e.
+it doesn't contain any error, and thus can be modified via the graphical interface),
 but not as an executable one, as there is nothing to execute.
 
 For display purposes, the JSON file may contain an additional field called
@@ -318,7 +318,7 @@ Putting it all together: a complete example
    A complete toolchain that train and test an Eigenfaces system
 
 The following example describes the toolchain visible at
-:numref:`beat-core-toolchains-example-figure`, a complete toolchain that:
+:numref:`beat-system-toolchains-example-figure`, a complete toolchain that:
 
   #. train an Eigenfaces face recognition system on one set of images (*train*)
   #. enroll client-specific models on another set of images (*templates*)