Unfix typography for autolinking.

"the script block's source" can't be autolinked, as the single quote is
typographized into a curly quote before autolinking. This patch unfixes
the typography before passing the string into 'getRef'.
Unfix typography before creating local definition text.
Present-participlize link text.

"Generating" should link to "Generate". "Navigating" should link to
"Navigate". "Linking" should link to "Link". And so on(ing).
Merge pull request #152 from mikewest/presentparticiplizing

Present-participlize link text.
Merge pull request #151 from mikewest/unfix

Unfix typography for autolinking.
Fold whitespace when getting the textContent of an element.

If definitions span lines, for example, the whitespace following
the newline is meaningful when generating definition IDs and etc.
We should fold multiple whitespace characters into a single space
when generating the text content of nodes to avoid this issue.

Closes #153.
Unbreak IDL.