Allow Cog Creators to override the repository name present in Index installation commands

[cswimr]

This PR allows for Cog Creator to specify the name key in their repository's info.json file, to override the name retrieved from the repository's URL. This changes the repository install command listed underneath cog descriptions on the Index.
For example, the repository install command for https://coastalcommits.com/Sea/Cogs on the Index would change from:
repo add cogs https://coastalcommits.com/Sea/Cogs to repo add SeaCogs https://coastalcommits.com/Sea/Cogs.

I've compiled a list of repositories that would be affected by this change below (small changes like capitalization differences or a missing/present - won't be listed here):

• cogs -> SeaCogs
• discord_cogs -> Malarne - discord_cogs
• mr42-cogs -> Mr42
• Toxic-Cogs -> Toxic Cogs
• predacogs -> Predä Cogs
• Jumper-Plugins -> JumperCogs
• Flare-Cogs -> Flare's Cogs
• Flapjack-Cogs -> FlapJack Cogs
• pokecord-red -> Pokecord
• bounty-cogs -> cray-cogs.
• cray-cogs -> cray-cogs.
• kennnyshiwa-cogs -> Kennnyshiwa's Cogs
• FalcomBot-cogs -> Falcogs
• palmtree5-cogs -> palmtree5's cogs
• phen-cogs -> Phen-Cogs.
• wizard-cogs -> Space Wizards Cogs
• tmerc-cogs -> tmerc cogs

[Flame442]

As I said in discord, I don't think the name key is a good idea, due to the number of repos it would affect, especially considering your research has found many cases of broken behavior if this were to be done. Downloader only accepts A-z, numbers, underscores, hyphens, and dots for the repo name, and most of the repos that have a name key currently are breaking at least one of those rules.

Additionally, capitalization changes are important, as on operating systems with case sensitive filepaths, two distinct capitalizations are distinct repo installations (see #6371). Someone who previously installed a cog from a repo attempting to follow the instructions on the index for a new cog would need to use the previously used name/capitalization or spend time determining the name that was used previously (which is what the autofilled name attempts to avoid them needing to do).

[cswimr]

Yeah, if Downloader doesn't accept spaces or other special characters, this change would be quite problematic lol - could use a different info.json key I suppose, index_name maybe? And fair enough on the capitalization thing, I was unaware of that.

[Twentysix26]

I don't think using the repo info.json's "name" field is a good solution as historically (in v2) it was supposed to be a human friendly repo name. In v3 it's been unused, albeit still present in the documentation.
Also, this PR as it is would break user expectations, because index consumers expect the "name" field to simply be the repo's actual name and for it to be a name with no invalid characters, as it's been the case for the past three years.

Personally, still a -1 even with a different field, because I think repositories should be named meaningfully in the first place :P