update readme/previews and add generate data method

README.md

@@ -6,13 +6,37 @@ The algorithm reads student requests and generates a timetable for all requested
 
 The algorithm has been moved out of `tinker.py` into its own python script. Version 1 and 2 are removed and the script can be found in the `/scheduleGenerator` folder. The algorithm has come a long way; using real 2018 course selection data from my school, enabling me to better test the script. V3 has a entirely different approach from V1 and V2, that you can read about at the top of the function in [`generator.py`](/scheduleGenerator/generator.py). The function is broken up into 6 steps, each step is labeled within the function with a comment, giving a brief explination of what that step contributes to the algorithm.
 
-This is the output after running it with the following command
+Here is the list of commands.
+1. Collect latest data from files and generate timetable
 ```
   $ ./tinker.py
 ```
 
+2. Collect Data and store it in files for later
+```
+  $ ./tinker.py generate_data
+```
+
+3. Generate timetable from existing files (faster), requires last command run
+```
+  $ ./tinker.py no_refresh
+```
+
+4. More details on errors
+```
+  $ ./tinker.py errors
+```
+
+<br>
+
+This is the output after running it with the following command.
+```
+  $ ./tinker.py no_refresh
+```
+
 ![preview](/preview/generator-preview.png)
 
+<br>
 
 A more in depth error log can be read with the additional argument
 ```