Change to golang style vars and statements

Based on feedback from @bradfitz,
* Change variable name to camelCase
* use assignment and check in the if block
* Use %q instead of %s to print useful error message

Author: cnu

consistenthash/consistenthash_test.go

@@ -36,9 +36,8 @@ func TestHashing(t *testing.T) {
 
 	// Get a value before any key is added to the hash
 	// Should yield an empty string
-	empty_value := hash.Get("empty key")
-	if empty_value != "" {
-		t.Errorf("Expecting empty string, got %s", empty_value)
+	if emptyHashValue := hash.Get("empty hash key"); emptyHashValue != "" {
+		t.Errorf("Get on an empty hash = %q; want empty string", emptyHashValue)
 	}
 
 	// Given the above hash function, this will give replicas with "hashes":