Replace app.UseModules by app.UseOrchardCore in OrchardCore.Modules documentation
Replace app.UseModules by app.UseOrchardCore in OrchardCore.Modules documentation

Fixes #1908

xkproject/Orchard2,stevetayloruk/Orchard2,stevetayloruk/Orchard2,petedavis/Orchard2,stevetayloruk/Orchard2,stevetayloruk/Orchard2,OrchardCMS/Brochard,OrchardCMS/Brochard,xkproject/Orchard2,petedavis/Orchard2,xkproject/Orchard2,xkproject/Orchard2,OrchardCMS/Brochard,petedavis/Orchard2,stevetayloruk/Orchard2,petedavis/Orchard2,xkproject/Orchard2