Docs: Charts Clean-up Effort: globals

As per https://gitlab.com/charts/gitlab/issues/1143, this is one part of many updates to the documentation for specific charts. WIP for now, while I cross-check the different chart changes and ask questions.

Included here: globals chart doc (large)

The settings were grouped together in a more compact way and alphabetized to make it easier to find the information. This is also how many other Docs are done in CE/EE documentation. I added the Defaults that are clearly listed, and attempted to add the Types for each parameter as well, but there may still be some blanks. If they need to be filled (or can be kept blank), let me know in a comment. I was not positive on all the types, so please check those carefully.

I also double checked all the backticks in setting lists and the usage of the special NOTE: formatting throughout. 😉