Set Zotero.automatedTest flag instead of .noUserInput on Travis

And don't skip alerts in Zotero.alert() during automated tests. (That
was intended to avoid long timeouts after unexpected failures, but,
e.g., PDF metadata lookups (which are currently disabled in automated
tests) should just be mocked so they don't intermittently fail.)

test/content/runtests.js

@@ -141,7 +141,7 @@ function Reporter(runner) {
 			// Dark red X for errors
 			+ "\033[31;40m" + Mocha.reporters.Base.symbols.err + " [FAIL]\033[0m"
 			// Trigger bell if interactive
-			+ (Zotero.noUserInput ? "" : "\007")
+			+ (Zotero.automatedTest ? "" : "\007")
 			+ " " + test.title + "\n"
 			+ indentStr + "  " + err.toString() + " at\n"
 			+ err.stack.replace(/^/gm, indentStr + "    "));