Pretty URLs support

The only forum system that does not support this feature is phpBB...
For example with smf there were already ways to do it 15 years ago.

So for some time I have been thinking of some workaround to have that feature without so much work.

I share my idea about it:

1) All urls go through append_sid(), so I think the best thing would be to massively rename the function to url_generation()

2) The $params parameter support string and array. This way the old code would still work.

3) Gradually add where the url_generation() function is used the new values of params that can be used to make our url configurable.

Example:
if I want to transform

viewtopic.php?t=1&f=1 

In this

/f1-your-first-forum/t1-my-topic-titl

you only need to have the name of the forum and the topic in this url_generation() calls

I think that with an approach like this you could have the feature quickly and it can be gradually improved