Enhance the directionalCombo to support sidewalk=both|left|right

[tordans]

In openstreetmap/id-tagging-schema#454 (comment) we came to the conclusion to add support to display sidewalk data on highway values.

There are three tagging schema in use. We support two already, but need to add the third one (which is in use 2.248.360 times).

In #9587 the directionalCombo was improved to support two of the variations. We now want to add the third which only applies to the sidewalk tag.

• Support sidewalk=both => and display it as sidewalk=yes (which is sidewalk:both=yes)
• Support sidewalk=left => and display it as sidewalk:left=yes
• Support sidewalk=right => and display it as sidewalk:right=yes