search: trim trailing whitespace (#184)

When amfora is given a string to search, if that string contains a
valid protocol (gemini://), and that string contains trailing
whitespace, then the string is treated as a search term.

Although perhaps slightly more uncommon, if the input string was as a
result of copy/paste then it's possible the string could contain
trailing spaces, which is not what was intended, but rather should be
removed so that it's treated either as a valid gemini:// link or a
search term.

Some efforts around this appeared in #138

display/display.go

@@ -198,6 +198,11 @@ func Init(version, commit, builtBy string) {
 				} else {
 					// It's a full URL or search term
 					// Detect if it's a search or URL
+
+					// Remove whitespace from the string.
+					// We don't want to convert legitimate
+					// :// links to search terms.
+					query := strings.TrimSpace(query)
 					if (strings.Contains(query, " ") && !hasSpaceisURL.MatchString(query)) ||
 						(!strings.HasPrefix(query, "//") && !strings.Contains(query, "://") &&
 							!strings.Contains(query, ".")) && !strings.HasPrefix(query, "about:") {