Fixes 172: Sanitize tags when editing or creating a node

[reb1995]

Was able to replicate the error in #172.

[UploadQueue] Node operation failed (attempt 4): Failed to modify node: HTTP 400 - Cannot parse valid node from xml string         <osm>
          <node changeset="185871008" id="12663617731" version="3" lat="37.36582032009576" lon="-122.07795191049095">
            <tag k="camera:mount" v="pole"/>
            <tag k="camera:type" v="fixed"/>
            <tag k="man_made" v="surveillance"/>
            <tag k="manufacturer" v="Flock Safety"/>
            <tag k="manufacturer:wikidata" v="Q108485435"/>
            <tag k="surveillance" v="public"/>
            <tag k="surveillance:type" v="ALPR"/>
            <tag k="surveillance:zone" v="traffic"/>
            <tag k="wikimedia_commons" v="File:ALPR Los Altos Grant & Covington.jpg"/>
            <tag k="operator" v="Los Altos Police Department"/>
            <tag k="operator:wikidata" v="Q120751721"/>
            <tag k="direction" v="180"/>
          </node>
        </osm>. Fatal error: xmlParseEntityRef: no name at :11.

XML sanitization was previously only applied to user comments. This PR applies sanitization to tags as well. The current profiles don't include &s or free form texts boxes where users can add them, but if the & is added from the web or a custom profile, the node will be uneditable from the app.

This fixes that problem.

3 scenarios tested using OSM Sandbox. All passed.

• Creating a new node with an "&" in a text box.
• Editing a node to add a text box with "&"
• Moving a node with a text box that has an "&"