Average Word Length Validity Check

## Description
Snippets will now be flagged when they are out of the average word length range. That range is currently `5.1 +- 2`, so `3.1` to `7.1`. Flagged snippets will not be sent to the feed of any other user. 

In the future, the average word length for a class note will be changed dynamically based on the combined average word length of all the class snippets. This could be a job that runs once a day.

**This will need a database reload**

### Testing Considerations
* [x] General Testing - Try to hit all pages and most functions to ensure no errors
* [x] In Social Analysis, ensure a snippet average word length out of `3.1` to `7.1` is flagged and not sent to other users