Add trie.el
Minor fixes to commentaries, package headers, and whitespace

* queue.el: fix description of data structure in Commentary; add Maintainer
  header.

* queue.el, heap.el, tNFA.el, trie.el, dict-tree.el: trivial whitespace fixes.
trie.el, tNFA.el, dict-tree.el: minor package header and autoload fixes

* trie.el: remove emacs version dependency.

* tNFA.el: add missing autoload cookies.

* dict-tree.el: minor change to package description, to match the other data
structure packages.
Updated trie.el package to version 0.2.6
* trie.el (trie--node-data): Simplify.
* packages/trie/trie.el (edebug-prin1, edebug-prin1-to-string): Use
advice-add when available.