Fix voltage limits, add additional parameters, add timing

[BradyPlanden]

Here's the fix. Key points:

• The voltage condition for each step of the experiment needs to stay within the upper and lower possible terminal voltages for the defined electrodes. This can be checked by testing the OCP methods with the corresponding minimum and maximum sto values. For small applied current values, overpotentials can assumed to be zero, and the terminal voltage equation becomes $\text{V}_\text{terminal} = \text{V}_p - \text{V}_n$. I didn't complete this calculation (I'll leave it to you); however, the voltage values I've entered lie within the required range.
• Added the upper and lower cut-off voltages, initial positive electrode concentration, initial OCP values from the Prada2013 set (you might not want all of these).
• Change the model definition to SPMe from DFN. For the applied current values you are testing, the DFN isn't needed. You can save computational time by reducing to the SPMe. Double-check this still does everything you need in the sub-models though.
• Timing for 506 cycles is ~76 seconds on my machine.