Better organization on Entity Statement chapter

[eduperottoni]

On section 1.2 it's explicit that Entity Configuration and Subordinate Statements are types of Entity Statements. On the other hand, in chapter 3. Entity Statement it's not that easy to understand this. This section contains Subordinate Statement claims and Entity Configuration claims, all in the same list. It would be easier for the reader if this chapter was divided into two sections (one listing SS claims and the other listing EC claims), with a preceding list of common claims in the beggining of the chapter. Also, having one example for each type will be helpful.

What do you think? I can make a PR with the proposed modifications if you agree.

Thanks so far!

[MichaelFraser1999]

In the past, I have noted people struggling to differentiate between Subordinate Statements and Entity Configurations in discussions, so further clarification on the two would be a positive change IMHO

[selfissued]

I would do this as three subsections:

1. Claims that MUST or MAY appear in both kinds of entity statements
2. Claims that MUST or MAY appear in Entity Configurations but not Subordinate Statements
3. Claims that MUST or MAY appear in Subordinate Statements but not Entity Configurations

[eduperottoni]

I would do this as three subsections:

1. Claims that MUST or MAY appear in both kinds of entity statements
2. Claims that MUST or MAY appear in Entity Configurations but not Subordinate Statements
3. Claims that MUST or MAY appear in Subordinate Statements but not Entity Configurations

Ok, that sounds good for me.