Update github install instructions

Tweak RTB startup file to handle distro or github case

Author: petercorke

README.md

@@ -121,12 +121,10 @@ git clone https://github.com/petercorke/robotics-toolbox-matlab.git robot
 git clone https://github.com/petercorke/spatial-math.git smtb
 git clone https://github.com/petercorke/toolbox-common-matlab.git common
 make -C robot
-mv common/startup_rvc.m .
 ```
-
-Then, from within MATLAB
+The last command builds the MEX files and Java class files. Then, from within MATLAB
 ```matlab
->> cd rvctools  % this is the same folder as above
+>> addpath rvctools/common  %  rvctools is the same folder as above
 >> startup_rvc
 ```
 The second line sets up the MATLAB path appropriately but it's only for the current session.  You can either:

startup_rtb.m

@@ -50,15 +50,20 @@ function startup_rtb(tbpath)
     if ~exist('DHFactor')
         javaaddpath( fullfile(tbpath, 'java', 'DHFactor.jar') );
     end
+    p = fullfile(tbpath, 'simulink');
+    if exist(p, 'dir')
+        addpath( p );
+    end
     addpath( fullfile(tbpath, 'interfaces', 'VREP') );
     % add the contrib code to the path
     rvcpath = fileparts(tbpath);  % strip one folder off path
     p = fullfile(rvcpath, 'contrib');
     if exist(p, 'dir')
         addpath(p)
     end
+    
 
-    p = fullfile(tbpath, 'data', 'ARTE');
+    p = fullfile(tbpath, 'data', 'meshes');
     disp([' - ARTE contributed code: 3D models for robot manipulators (' p ')']);
     p = fullfile(rvcpath, 'contrib', 'pHRIWARE', 'next');
     if exist(p, 'dir')