Fix non ES5 regexp
Fix non ES5 regexp

ES5 appears to require that { be escaped when not used as part of a quantifier. While this works fine in browsers it appears to choke less lenient runtimes (e.g. Duktape)
hoverduck/mocha,beatfactor/mocha,tswaters/mocha,Shyp/mocha,jjoos/mocha,boneskull/mocha,adamgruber/mocha,jjoos/mocha,ELLIOTTCABLE/mocha,nightwatchjs/mocha-nightwatch,apkiernan/mocha,villesau/mocha,sul4bh/mocha,hoverduck/mocha,rlugojr/mocha,pumpupapp/mocha,aaroncrows/mocha,santiagoaguiar/mocha,adamgruber/mocha,aaroncrows/mocha,Shyp/mocha,pumpupapp/mocha,menelaos/mocha-solarized,ryanshawty/mocha,mochajs/mocha,sul4bh/mocha,ELLIOTTCABLE/mocha,villesau/mocha,Shyp/mocha,menelaos/mocha-solarized,beatfactor/mocha,ELLIOTTCABLE/mocha,beatfactor/mocha,hoverduck/mocha,mochajs/mocha,Hacker0x01/mocha,Khan/mocha,outsideris/mocha,santiagoaguiar/mocha,rlugojr/mocha,JohnnyEstilles/mocha,santiagoaguiar/mocha,nightwatchjs/mocha-nightwatch,apkiernan/mocha,Hacker0x01/mocha,menelaos/mocha-solarized,mochajs/mocha,aaroncrows/mocha,ryanshawty/mocha,tswaters/mocha,igwejk/mocha,hoverduck/mocha,Khan/mocha,boneskull/mocha,JohnnyEstilles/mocha,Hacker0x01/mocha,rlugojr/mocha,outsideris/mocha,ryanshawty/mocha,JohnnyEstilles/mocha,apkiernan/mocha,boneskull/mocha,igwejk/mocha,villesau/mocha,jjoos/mocha,nightwatchjs/mocha-nightwatch,pumpupapp/mocha,Khan/mocha,adamgruber/mocha,sul4bh/mocha,tswaters/mocha