Update readme to describe analysis

[SebastianZimmeck]

Currently, the readme explains the analysis by referring to the OptMeowt analysis mode:

It automatically runs OptMeowt Analysis mode on all the given sites of the input csv file in Firefox.

However, the analysis mode is no longer in the current version of OptMeowt. So, this may be slightly confusing (at least, I was confused, thinking that OptMeowt still has the analysis mode). Thus, @katehausladen, could you rewrite the crawler repo, to the extent necessary, describing what is currently described via the link in the OptMeowt repo? So, directly include in the crawler repo what is important to know.

[katehausladen]

There was an updated description of analysis functionality in the architecture section of the readme. I removed the OptMeowt Analysis mode reference at the beginning and pointed readers to that section for details on analysis functionality.