Refactor color sensor code to separate file

This change aims to modularize the robot code by moving the color sensor code to a separate file.

Summary of Changes

• Add color.h and color.cpp file
• Move all functions to the color files
• Move the global variables associated with color to color.cpp
• Add a calibrateWhite and calibrateBlack() function

include/color.h

@@ -23,15 +23,14 @@ typedef enum
     CALIBRATE_READY,
 } CalibrationState;
 
-extern CalibrationState calibration_state;
-
 void setupColorSensor();
 
 void printRGB(const Rgb &value);
 
-void getColorValues(Rgb &left_value, Rgb &right_value);
+void readColorValues(Rgb &left_value, Rgb &right_value);
 
 float computeHue(const Rgb &rgb);
 
+CalibrationState getCalibrationState();
 void calibrateBlack();
 void calibrateWhite();