Corrects typos and grammatical errors

Improves readability across documentation and inline comments by fixing common spelling mistakes and duplicate words.

src/helpers/NRF52Board.h

@@ -67,7 +67,7 @@ public:
 /*
  * The NRF52 has an internal DC/DC regulator that allows increased efficiency
  * compared to the LDO regulator. For being able to use it, the module/board
- * needs to have the required inductors and and capacitors populated. If the
+ * needs to have the required inductors and capacitors populated. If the
  * hardware requirements are met, this subclass can be used to enable the DC/DC
  * regulator.
  */

src/helpers/sensors/RAK12035_SoilMoisture.cpp

@@ -67,10 +67,10 @@ void RAK12035_SoilMoisture::setup(TwoWire &i2c)
 // setup() and that the bus has been initialized externally (Wire.begin()).
 // It uses the passed in I2C Address (default 0x20)
 //
-// ***  This code does not supprt three sensors ***
+// ***  This code does not support three sensors ***
 //      The RAK12023 has three connectors, but each of the sensors attached must
 //      all have a different I2C addresses.
-//      This code has a function to set the I2C adress of a sensor
+//      This code has a function to set the I2C address of a sensor
 //      and currently only supports one address 0x20 (the default).
 //      To support three sensors, EnvironmentSensorManager would need to be modified
 //      to support multiple instances of the RAK12035_SoilMoisture class,
@@ -78,7 +78,7 @@ void RAK12035_SoilMoisture::setup(TwoWire &i2c)
 //      The begin() function would need to be modified to loop through the three addresses
 //
 // DEBUG STATEMENTS: Can be enabled by uncommenting or adding:
-//      File:    varients/rak4631 platformio.ini
+//      File:    variants/rak4631 platformio.ini
 //      Section example: [env:RAK_4631_companion_radio_ble] 
 //      Enable Debug statements: -D MESH_DEBUG=1
 // 
@@ -107,7 +107,7 @@ bool RAK12035_SoilMoisture::begin(uint8_t addr)
  *      Change the value to 1 in the RAK12035_SoilMoisture.h file
  * 
  * Calibration Procedure:
- * 1) Flash the the Calibration version of the firmware.
+ * 1) Flash the Calibration version of the firmware.
  * 2) Leave the sensor dry, power up the device.
  * 3) After detecting the RAK12035 this firmware will display calibration data on Channel 3
  * 

src/helpers/ui/OLEDDisplay.cpp

@@ -846,7 +846,7 @@ void OLEDDisplay::drawLogBuffer(uint16_t xMove, uint16_t yMove) {
     if (this->logBuffer[i] == 10) {
       length++;
       // Draw string on line `line` from lastPos to length
-      // Passing 0 as the lenght because we are in TEXT_ALIGN_LEFT
+      // Passing 0 as the length because we are in TEXT_ALIGN_LEFT
       drawStringInternal(xMove, yMove + (line++) * lineHeight, &this->logBuffer[lastPos], length, 0, false);
       // Remember last pos
       lastPos = i;

src/helpers/ui/OLEDDisplay.h

@@ -60,7 +60,7 @@ private:
 };
 
 #else
-#error "Unkown operating system"
+#error "Unknown operating system"
 #endif
 
 #include "OLEDDisplayFonts.h"
@@ -160,7 +160,7 @@ class OLEDDisplay : public Print  {
 #elif __MBED__
 class OLEDDisplay : public Stream {
 #else
-#error "Unkown operating system"
+#error "Unknown operating system"
 #endif
 
   public: