Add Yuanpeng's k-vec tutorial after edits & apply ideas from that to FontSize

Author: briantoby

MDtutorials/FontSize/FontSize.md

@@ -28,29 +28,29 @@ and provide an example of what could be improved.
 The font size setting is applied when GSAS-II is started, so changing it requires 
 restarting GSAS-II before the effect of this setting is seen. 
 
-## 1. Finding the preferences settings
+## Finding the preferences settings
 
-![Select the preference menu](menu1.png)
+![Select the preference menu](imgs/menu1.png)
 
 The font setting is determined by preference variable `FontSize_incr` and this is set inside the File menu (File->Preferences). On MacOS, preference settings are also found in the usual App menu (labeled GSAS-II or python, depending on how the GSAS-II GUI is started), as shown here.
 
-## 2. Change the font preference value
+## Change the font preference value
 
-![Opening the preference menu](dialog1.png)
+![Opening the preference menu](imgs/dialog1.png)
 
 When the Preferences menu is selected a window is opened where any of 
 the preference variables can be selected. Select from the pull-down
 list the variable `FontSize_incr` as shown here.
 
-![Setting the font size preference](dialog2.png)
+![Setting the font size preference](imgs/dialog2.png)
 
  This will open a window where the value can be set for the font
  size. Note that a value of 0 (the default) provides the
  system-default size for the font. A positive value provides a larger
  font and a negative value provides a smaller font. Only integer
  values can be used. 
 
-![Set if GSAS-II should be restarted](restart.png)
+![Set if GSAS-II should be restarted](imgs/restart.png)
 
 As noted before, the value set for  `FontSize_incr` is applied only
 when the GSAS-II application is started, so when the "Save current
@@ -60,7 +60,7 @@ choose "No" here; the change will take effect the next time that
 GSAS-II is started. If "Yes" is selected, you will get the chance to
 save the current GSAS-II project. 
 
-![Set if the project needs to be saved](save.png)
+![Set if the project needs to be saved](imgs/save.png)
 
 When "Yes" is above, the window here is shown to ask if you want to
 save any changes made to the current GSAS-II project file. 
@@ -75,15 +75,15 @@ save any changes made to the current GSAS-II project file.
   you will be asked for a location and name for the .gpx file. GSAS-II
   will then restart with the saved version of the project loaded. 
 
-## 3. Example with the changed font size
+## Example with the changed font size
 
 Below are two examples of GSAS-II with two different font size
 settings.
 
 |  `FontSize_incr`  | Example |
 | :---: | ------------------------------------- | 
-| 0 | ![Example of GSAS-II GUI with the default font size (font=0)](font0.png) |
-| 3 | ![Example of GSAS-II GUI with the font increased by 3 units (font=3)](font3.png) |
+| 0 | ![Example of GSAS-II GUI with the default font size (font=0)](imgs/font0.png) |
+| 3 | ![Example of GSAS-II GUI with the font increased by 3 units (font=3)](imgs/font3.png) |
 
 Note that not all text (for example the status message at the bottom
 of the window) has the font size changed.