doxygen: add groups for all modules

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

src/lcd/i2clcd.h

@@ -72,6 +72,10 @@ namespace upm {
 #define LCD_RW 0x02 // Read/Write bit
 #define LCD_RS 0x01 // Register select bit
 
+/**
+ * @brief i2c LCD display library
+ * @defgroup i2clcd libupm-i2clcd
+ */
 class I2CLcd {
     public:
         I2CLcd (int bus, int lcdAddress);

src/lcd/jhd1313m1.h

@@ -38,6 +38,7 @@ namespace upm {
  * [Grove LCD RGB Backlight v2.0 display]
  * (http://www.seeedstudio.com/depot/Grove-LCD-RGB-Backlight-p-1643.html?cPath=34_36)
  *
+ * @ingroup i2clcd
  * @snippet rgb-lcd.cxx Interesting
  * @image html grovergblcd.jpeg
  */

src/lcd/lcm1602.h

@@ -42,6 +42,7 @@ namespace upm {
  * [TC1602A-01T](https://www.adafruit.com/datasheets/TC1602A-01T.pdf) seems to
  * the best documented example.
  *
+ * @ingroup i2clcd
  * @snippet lcm-lcd.cxx Interesting
  * @image html lcm1602.jpeg
  */

src/lcd/ssd1308.h

@@ -155,6 +155,7 @@ typedef enum {
  * (http://www.seeedstudio.com/wiki/Grove_-_OLED_Display_0.96%22)
  * which is an OLED monochrome display
  *
+ * @ingroup i2clcd
  * @snippet oled-1308.cxx Interesting
  * @image html ssd1308.jpeg
  */

src/lcd/ssd1327.h

@@ -155,6 +155,7 @@ typedef enum {
  * (http://www.seeedstudio.com/wiki/Grove_-_OLED_Display_1.12%22)
  * which is an OLED monochrome display
  *
+ * @ingroup i2clcd
  * @snippet oled-1327.cxx Interesting
  * @image html ssd1327.jpeg
  */