fix links enabling

[kmike]

In link enabling code toRemove and toPush objects were created inside a loop that iterates over attributes. They should be created in a level above, in a loop that iterates over elements. This caused two issues:

1. only last attribute was enabled (that was not a problem because usually there is only one such attribute);
2. toRemove and toPush objects were not cleaned for elements without attributes - this causes unrelated elements (e.g. a <span> tag inside <a href="..."> tag) to get href attributes from the previous elements.