Update Gallery Part II

[prisae]

In #217 Part I was done: frequency domain; reproducing; and published. Here the missing ones:

Update Gallery

• Replace LaTeX in figures by unicode symbols
• Replace implicit by explicit pyplot (OO)
• Use by default coordinate system with positive z upwards

To Do

• time_domain
  • cole_cole_ip.py
  • dc_rho-a_dip-dip.py
  • note_for_land_csem.py
  • step_and_impulse.py
  • tem_walktem.py
• educational
  • coordinate_system.py
  • dipoles_and_loops.py
  • dlf_design.py
  • dlf_standard_lagged_splined.py
  • halfspace_vs_dipole.py
  • ht_ft_with_other_modellers.py
  • random_noise_f_domain.py
  • tmte_split.py