BME280: Add string based constructor

Signed-off-by: Adelin Dobre <adelin.dobre@rinftech.com>

src/bmp280/bme280.cxx

@@ -41,6 +41,12 @@ BME280::BME280(int bus, int addr, int cs) :
 {
 }
 
+BME280::BME280(std::string initStr) :
+  BMP280(initStr)
+{
+}
+
+
 BME280::~BME280()
 {
 }

src/bmp280/bme280.hpp

@@ -83,6 +83,13 @@ namespace upm {
         BME280(int bus=BME280_DEFAULT_I2C_BUS, int addr=BME280_DEFAULT_ADDR,
                int cs=-1);
 
+        /**
+         * Instantiates BME280 Digital Sensor based on a given string.
+         *
+         * @param initStr string containing specific information for BME280 initialization.
+         */
+        BME280(std::string initStr);
+        
         /**
          * BME280 Destructor.
          */