Improve New Mod Name During Creation

[JohnAFernandez]

1) Remove the regex replace for mod names, as there is no restriction in the mod dev details tab.

2) Automatically replace spaces with underscores in the modID

3) Keep track of whether the user has manually set the ModID, and stop automatically setting the ModID from the mod name, if so.

Tested.

Fixes #151 In draft until I hear back from ShivanSpS about whether having arbitrary characters in the mod name is supported by Nebula.

[notimaginative]

I don't believe there is any restriction on mod names, just the mod id. Aside from length, nebula itself doesn't limit content on either even though mod id requires a limited character set. Old-knossos does a regex check on the mod id but has no restriction on the name.

[JohnAFernandez]

I'll mark it as ready for review, then. Looks like the regex replace on the mod name was a just a small mistake.