More robust handing of _ in URL

[Ducasse]

\pub \czauthors{Mart'in Dias and St'ephane Ducasse and Damien Cassou and Uquillas G'{o}mez, Ver'{o}nica}, \cztitle{Do Tools Support Code Integration? A Survey}, In \czjournal{Journal of Object Technology}, Volume 16, pp. 2:1-20, 2016, http://www.jot.fm/issues/issue_2016_02/article2.pdf, 10.5381/jot.2016.15.2.a2.

should be transformed into

\pub \czauthors{Mart'in Dias and St'ephane Ducasse and Damien Cassou and Uquillas G'{o}mez, Ver'{o}nica}, \cztitle{Do Tools Support Code Integration? A Survey}, In \czjournal{Journal of Object Technology}, Volume 16, pp. 2:1-20, 2016, http://www.jot.fm/issues/issue\_2016\_02/article2.pdf, 10.5381/jot.2016.15.2.a2.

We should check if we can extract the HTMLCanvas from Pillar.