Implements Better Error Messages from the HAL (#172)

* Makes the HAL provide a better error message for certain things.

* Makes Java error messages better

* Updates C++ errors.

* Moves handles header folder to HAL directory

hal/lib/shared/handles/HandlesInternal.cpp

@@ -0,0 +1,35 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2016. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "HAL/handles/HandlesInternal.h"
+
+namespace hal {
+HAL_PortHandle createPortHandle(uint8_t pin, uint8_t module) {
+  // set last 8 bits, then shift to first 8 bits
+  HAL_PortHandle handle = static_cast<HAL_PortHandle>(HAL_HandleEnum::Port);
+  handle = handle << 24;
+  // shift module and add to 3rd set of 8 bits
+  int32_t temp = module;
+  temp = (temp << 8) & 0xff00;
+  handle += temp;
+  // add pin to last 8 bits
+  handle += pin;
+  return handle;
+}
+
+HAL_Handle createHandle(int16_t index, HAL_HandleEnum handleType) {
+  if (index < 0) return HAL_kInvalidHandle;
+  uint8_t hType = static_cast<uint8_t>(handleType);
+  if (hType == 0 || hType > 127) return HAL_kInvalidHandle;
+  // set last 8 bits, then shift to first 8 bits
+  HAL_Handle handle = hType;
+  handle = handle << 24;
+  // add index to set last 16 bits
+  handle += index;
+  return handle;
+}
+}  // namespace hal