Add config option "disablePathToLower"

Enabling this prevents lowercasing of the path/url.

Fixes #557

commands/hugo.go

@@ -160,6 +160,7 @@ func LoadDefaultSettings() {
 	viper.SetDefault("Blackfriday", helpers.NewBlackfriday())
 	viper.SetDefault("RSSUri", "index.xml")
 	viper.SetDefault("SectionPagesMenu", "")
+	viper.SetDefault("DisablePathToLower", false)
 }
 
 // InitializeConfig initializes a config file with sensible default configuration flags.