Modified Node.clone() to use iterative approach.

Uses BFS to clone nodes. Fixes #290.
Merge branch 'master' into issue_290
Added test for cloning deeply nested document.

Based on @khaing211's suggestion and test code. The test is ignored by default since it can take awhile to run.
Add "cite" protocols to relaxed

This option is present in basic but missing from relaxed.
Fixed support for self-closing script tags.

Fixes #305
Fixed a crash when reading an unterminated CDATA section.

Fixes #349
Fixed an issue where elements added via the adoption agency algorithm did not preserve their attributes.

Fixes #313
Added test for #332, already passes without pull
Tweaked Elements.clone()

So that extenders' clones will be the correct type.
FindBugs squash

Document that extenders equals method is just ==
Merge pull request #351 from marconilanna/patch-1

Add "cite" protocols to relaxed
Merge branch 'pr/292'
Changelog for #290
Merge remote-tracking branch 'upstream/master'
1. add unit test to verify wok of disabling security
2. adjust class instance check
1. got ignore annotation back
2. add java doc to unit test