feat: detailed results for calculate strain profile

[talledodiego]

With this PR I implemented custom results for calculate_strain_profile.

The objects store information (some are calculated only if and when requested) to assess the convergence process, e.g. the following lines:

plt.semilogy(strain_res.residual_norm_history, "-o")
plt.ylabel(r"$||\mathbf{r}||$")

plot the norm of the residual vector:

A future PR will assess the results for integrate_strain_profile

[mortenengen]

Thanks for this useful contribution!