Finish minimal documentation for all modules

[matthewhammer]

Finish writing at least one line of description for each method in the module or class below:

• Buf (rename to Buffer?)
• Array -- Documentation for Array module #138
• Deque -- Document Deque module #132
• Hashmap
• RBTree -- Documentation for RBTree module #140
• Trie -- Document more of Trie module; clean up. #130
• TrieMap -- Docs for TrieMap module #128
• TrieSet -- Document TrieSet module #139
• AssocList -- Finish documentation for AssocList module #141

cc @crusso @kritzcreek @rossberg

[kritzcreek]

HashMap done in #121

[crusso]

@matthewhammer Any progress here? Would help out but have other fires to put out...

[matthewhammer]

@crusso I have time today for this. I'll get to it all this week. Sorry for the delays.

[matthewhammer]

(Finally) made a PR for this.

I started with TrieMap #128 to get used to the workflow and it seems very nice. I have one question, which I put there in the PR.

Seems easy enough to finish the rest today this week.

[matthewhammer]

Update: PRs are open for each module in the list, but many need a review.