Stop MathJax queue when loading new page
Stop MathJax queue when loading new page

In order not to slow down navigating forwards and backwards through the
history, this stops the MathJax processing queue when a webview navigates
to a new page.

[endlessm/eos-sdk#2152]

endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib