Configurable host:port (#7)

* replyParser had a bug where, when a base64 address ended with '==', the key-value pairs would break. I worked around the issue by switching '==' it with a non-base64 character before the split, and back after.

* switch to strings.SplitN and apply gofmt, add test

* I don't know exactly why, but checking that the kvPair in replyParser.go is not nil fixes the crash on image-heavy sites.

* added new configuration options for host, port, address, and debugging

* Fix commit history

* added tunnel length control features

* added tunnel length control defaults

* added length variance feature

* added tunnel quantity option

* added backup tunnel quantity option

* added leaseset configuration options

* gofmt

* add new options to session establishment commands & gofmt

* Reference the change to the debug global in the httpTest.go example

* Switch to less than or equal to 16 tunnels at a time.

* add in the comments I forgot to do.

* add in the comments I forgot to do.

* Improved formatting with linter.

* Improved formatting with linter.

* Ditch interfaces in the functional arguments, instead use different functions for the string and int-based variations.

* Fixed broken option

* added in missing formatting directive.

* change addr to host in client so names are consistent.

* change TestClientLookupInvalid back.

client_test.go

@@ -7,10 +7,8 @@ var client *Client
 func setup(t *testing.T) {
 	var err error
 
-	ConnDebug = true
-
 	// these tests expect a running SAM brige on this address
-	client, err = NewDefaultClient()
+	client, err = NewClientFromOptions(SetDebug(true))
 	if err != nil {
 		t.Fatalf("NewDefaultClient() Error: %q\n", err)
 	}