Deprecate the suppressLoadErrors option

This was intended as a 3.0 migration aid for browser users who had
dependencies that triggered errors at load time. However, it was never
documented and never supported by jasmine-brower-runner, karma, or any
other commonly used tool for runing Jasmine in the browser. There is
no evidence of it actually being used. It is, however, starting to
show up in machine-generated "tutorials".

spec/core/EnvSpec.js

@@ -634,6 +634,10 @@ describe('Env', function() {
   });
 
   describe('when constructed with suppressLoadErrors: true', function() {
+    beforeEach(function() {
+      spyOn(console, 'error'); // prevent deprecation from being logged
+    });
+
     it('does not install a global error handler until execute is called', function() {
       const globalErrors = jasmine.createSpyObj('globalErrors', [
         'install',