Fixes for ResourceLoaderWikiModule r72776. No serious bugs found, do not merge before...

Fixes for ResourceLoaderWikiModule r72776. No serious bugs found, do not merge before deployment.
* Specify page titles as strings instead of split NS/DBK, as suggested by Roan on CR. It seemed sensible to me.
* Pass a Title object to getContent() instead of a string, to avoid unnecessary object construction overhead
* "*" and "/" are valid title characters. Check module input for JS comment end tokens.
* Fixed inappropriate conversion to boolean, when checking result of getContent(). Presumably the idea was to omit empty sections and errors, so that's what I did. Maybe an informative error message would be better in the error case.
* Use LinkBatch for selecting multiple page rows instead of Database::makeWhereFrom2d().
* Fixed assignment expression.