restarting needs maintenance

[yigu8115]

I haven’t added these to the simulation-restarting part yet:
https://github.com/BrainDynamicsUSYD/SpikeNet/blob/master/matlab_interface/writeExtConductanceTimeVariantSettingsHDF5.m
https://github.com/BrainDynamicsUSYD/SpikeNet/blob/master/matlab_interface/writeExtCurrentTimeVariantSettingsHDF5.m

This means if you use these two new features together with restarting, shit will happen.

We need a thorough check there if we still want to use the restarting feature