examples: Fix samples.mapping
Fix samples.mapping.txt with the cleaned-up C++ examples
-AioA0.cpp java/AioA0.java
-Blink-IO.cpp java/BlinkIO.java
-I2c-compass.cpp java/I2cCompass.java
-Pwm3-cycle.cpp java/CyclePwm3.java
-Spi-pot.cpp java/SpiMCP4261.java
-Uart-example.cpp java/UartExample.java
+aio.cpp java/AioA0.java
+gpio.cpp java/BlinkIO.java
+i2c.cpp java/I2cCompass.java
+pwm.cpp java/CyclePwm3.java
+spi.cpp java/SpiMCP4261.java
+uart.cpp java/UartExample.java
