LUA API documentation is lacking

Having FSO output the scripting.html is a novel idea to keep modders up to date on what functions they have access to, but to be honest the result is very user unfriendly and everything isn't documented adequately.

One particular example is that the numerous Enumerations at the bottom of the scripting.html have no information on what exactly they do, or for that matter suggest some of the precautions a modder has to take in order for them to work correctly. This let to issues such as #4108 to occur