Don't URL-encode most characters in DOIs when opening/copying as link

Only #, ?, and % are now encoded.

Addresses #295

chrome/content/zotero/bindings/itembox.xml

@@ -428,7 +428,11 @@
 							// Pull out DOI, in case there's a prefix
 							var doi = Zotero.Utilities.cleanDOI(val);
 							if (doi) {
-								doi = "https://doi.org/" + encodeURIComponent(doi);
+								doi = "https://doi.org/"
+									// Encode some characters. '/' doesn't need to be encoded
+									+  doi.replace(/#/g, '%23')
+										.replace(/\?/g, '%3f')
+										.replace(/%/g, '%25');
 								label.classList.add("pointer");
 								label.setAttribute("onclick", "ZoteroPane_Local.loadURI('" + doi + "', event)");
 								label.setAttribute("tooltiptext", Zotero.getString('locate.online.tooltip'));