LetMeCreate 1.5.0

Changes from previous version:

• Add support for Lora Click in point-to-point mode
• Various fixes in led, gpio and pwm
• Fix UART carriage return character from getting transformed into line feeds
• Add i2c timeout
• Add examples for switch wrapper, uni_hall and lora
• API change in alphanum click wrapper to get rid of manually selecting each display
• Add extern "C" in each header to mix LetMeCreate with C++
• Add SPI get maximum transfer length