File re-organization. New Makefile.

- Re-organized source code files into a ‘grbl’ directory to lessen one
step in compiling Grbl through the Arduino IDE.

- Added an ‘examples’ directory with an upload .INO sketch to further
simplify compiling and uploading Grbl via the Arduino IDE.

- Updated the Makefile with regard to the source code no longer being
in the root directory. All files generated by compiling is placed in a
separate ‘build’ directory to keep things tidy. The makefile should
operate in the same way as it did before.

grbl/print.h

@@ -0,0 +1,58 @@
+/*
+  print.h - Functions for formatting output strings
+  Part of Grbl v0.9
+
+  Copyright (c) 2012-2015 Sungeun K. Jeon
+
+  Grbl is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Grbl is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with Grbl.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/* 
+  This file is based on work from Grbl v0.8, distributed under the 
+  terms of the MIT-license. See COPYING for more details.  
+    Copyright (c) 2009-2011 Simen Svale Skogsrud
+    Copyright (c) 2011-2012 Sungeun K. Jeon
+*/ 
+
+#ifndef print_h
+#define print_h
+
+
+void printString(const char *s);
+
+void printPgmString(const char *s);
+
+void printInteger(long n);
+
+void print_uint32_base10(uint32_t n);
+
+void print_uint8_base2(uint8_t n);
+
+void print_uint8_base10(uint8_t n);
+
+void printFloat(float n, uint8_t decimal_places);
+
+// Floating value printing handlers for special variables types used in Grbl. 
+//  - CoordValue: Handles all position or coordinate values in inches or mm reporting.
+//  - RateValue: Handles feed rate and current velocity in inches or mm reporting.
+//  - SettingValue: Handles all floating point settings values (always in mm.)
+void printFloat_CoordValue(float n);
+
+void printFloat_RateValue(float n);
+
+void printFloat_SettingValue(float n);
+
+// Debug tool to print free memory in bytes at the called point. Not used otherwise.
+void printFreeMemory();
+
+#endif