[xwiki-devs] [Proposal] Disallow / and \ in page names by default

Hi devs, Because of tomcat and because tomcat is by far the most used container for xwiki and because we also bundle tomcat in the debian and docker dsitributions, I think we should disallow / and \ in page names by default. It's causing too much trouble for users. We keep having users posting problems and for one user who post a problem there are 100 who don't. The latest one: https://forum.xwiki.org/t/please-help-broken-link-routing-cannot-open-page-… Implementation idea: * Offer an extension point in the create page UI to allow plugging some cleaning algorithm * Provide the \ and / cleaning algorithm by default * Handle backward compat. Find ways to not break existing users who are having / and \ in page names. For example we could imagine a property in xwiki.properties that we would set to point to the hint of the / and \ cleaner component. Thus existing users would need to voluntarily upgrade their xwiki.properties to have it if they want it. We would need to provide some script to convert existing pages with / and \ too probably. WDYT? Thanks -Vincent