hugolib: Fix handling of taxonomy terms containing slashes

This commit attempts to sanitize term keys and path segments to fix the
handling of taxonomy terms containing slashes.

Based upon gohugoio#4092 by @tsuereth.

Fixes gohugoio#4090

hugolib/hugo_sites.go

@@ -453,7 +453,7 @@ func (h *HugoSites) createMissingPages() error {
 						origKey := key
 
 						if s.Info.preserveTaxonomyNames {
-							key = s.PathSpec.MakePathSanitized(key)
+							key = s.PathSpec.MakeSegment(key)
 						}
 						for _, p := range taxonomyPages {
 							// Some people may have /authors/MaxMustermann etc. as paths.

hugolib/page_paths.go

@@ -193,7 +193,13 @@ func createTargetPath(d targetPathDescriptor) string {
 		if d.ExpandedPermalink != "" {
 			pagePath = filepath.Join(pagePath, d.ExpandedPermalink)
 		} else {
-			pagePath = filepath.Join(d.Sections...)
+			pagePath = ""
+			for i, section := range d.Sections {
+				if i > 0 {
+					pagePath += helpers.FilePathSeparator
+				}
+				pagePath += d.PathSpec.MakeSegment(section)
+			}
 		}
 		needsBase = false
 	}