hotfix: --no_fs_t1 lower case

[m-reuter]

closes #324

[LeHenschel]

So if you want to do the fix this way around (changing it in recon_surf.sh), the documentation needs to be updated as well. Both in recon_surf.sh and run_fastsurfer.sh the flag is described with upper case. Otherwise, it would have been easier to change it in run_fastsurfer.sh because this is the only place where the T was lower case.

[m-reuter]

I thought, when we check for parameters, we always convert the input to lower case and then compare the strings in lower case format. That is why I changed it like this.

[LeHenschel]

Ok, I see. Then it makes sense. I was not aware of the new changes there.