templateHelper.js: longnameToUrl, getSignatureParams, getSignatureType tests added
jsdoc/util/templateHelper: added getSignatureReturns, registerLink, resolveAuthorLinks, getAncestorLinks tests
FEATURE/FIX: jsdoc/util/templateHelper.getAncestorLinks: direct parents punctuation should be part of the link text. <a href="">Parent~</a> vs <a href="">Parent</a>~