Merge tessel#17 r=@jiahuang: Added tests for the get/set pollTime

I figured out my issues. It has been a long time since I have seen the TAP protocol and completely forgot how it was supposed to work.

test/getSetPollTime.js

@@ -0,0 +1,84 @@
+
+var tessel = require('tessel');
+
+var port = process.argv[2] || 'C';
+var gps = require('../').use(tessel.port[port]);
+var exitStatus = 0;
+
+console.log('# testing on port', port);
+console.log('1..9');
+
+// Test default setting
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting default poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - default poll time is 2000');
+}
+
+// Test set to a value
+gps.setPollTime(4473);
+if (gps.getPollTime() !== 4473) {
+    console.log('not ok - expecting poll time to be 4473, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 4473 after being set to 4473');
+}
+
+// Test minimum value
+gps.setPollTime(1999);
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting minimum poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 2000 after being set to 1999');
+}
+gps.setPollTime(55);
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting minimum poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 2000 after being set to 55');
+}
+
+// Test maximum value
+gps.setPollTime(60001);
+if (gps.getPollTime() !== 60000) {
+    console.log('not ok - expecting maximum poll time to be 60000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 60000 after being set to 60001');
+}
+gps.setPollTime(8899983);
+if (gps.getPollTime() !== 60000) {
+    console.log('not ok - expecting maximum poll time to be 60000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 60000 after being set to 8899983');
+}
+
+// Test invalid values
+gps.setPollTime("testing");
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting fallback poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 2000 after being set to testing');
+}
+gps.setPollTime({time: 4000});
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting fallback poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 2000 after being set to testing');
+}
+gps.setPollTime(function () { return 4000;});
+if (gps.getPollTime() !== 2000) {
+    console.log('not ok - expecting fallback poll time to be 2000, the value is', gps.getPollTime());
+    exitStatus = 1;
+} else {
+    console.log('ok - poll time is 2000 after being set to testing');
+}
+
+process.exit(0);
+