examples: C/C++ examples use transitive dependencies

Updated the examples to comprehend transitive dependencies.  This means
that each example target will no longer have a giant list of -I includes
(the examples at the end of the list had includes for all previous
examples, upwards of 200 -I's on the command line).

    * Created a CMakeLists.txt in the upm/examples directory, moved
      common functionality to this level.
    * C/C++ examples now look to the filename for their dependency
      target name, ie; gas-mq2.cxx adds a dependency to the 'gas' target
    * Updated a handful of C/C++ example names to reflect this
    * Example CMake flow - glob the list of files, add targets for any
      special case examples, then att targets for all the rest

Signed-off-by: Noel Eck <noel.eck@intel.com>

examples/c++/grove-groveled-multi.cxx

@@ -0,0 +1,68 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2014-2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <unistd.h>
+#include <iostream>
+#include <signal.h>
+#include "grove.hpp"
+
+using namespace std;
+
+int shouldRun = true;
+
+void sig_handler(int signo)
+{
+  if (signo == SIGINT)
+    shouldRun = false;
+}
+
+
+int main()
+{
+  signal(SIGINT, sig_handler);
+
+//! [Interesting]
+
+  // Instantiate a grove LED on D2.  Here we are controlling a Grove
+  // Multi-color flash LED.  We just just need to turn it on - it will
+  // then cycle through various colors (red, green, blue, purple) on it's
+  // own until turned off.
+  upm::GroveLed* led = new upm::GroveLed(2);
+
+  // start the light show
+  led->on();
+
+  // just sleep until interrupted
+  while (shouldRun)
+    sleep(1);
+  
+//! [Interesting]
+
+  led->off();
+  cout << "Exiting..." << endl;
+
+  delete led;
+  
+  return 0;
+}