1. in tos_at.h, added int fuzzy_matching; field into at_echo_st struct, if this field is set to K_TRUE, then if echo message contains the string in "echo_expect" field.
2. added __API__ int tos_at_echo_fuzzy_matching_create(at_echo_t *echo, char *buffer, size_t buffer_size, char *echo_expect_contains) api to tos_at.c, which will create an at_echo_t with fuzzy_matching = K_TRUE;
3. added RHF76_ATCMD_SET_DELAY and rhf76_set_delay to RHF76.h to allow set/query RX delay config
4. added RHF76_ATCMD_SET_DATA_RATE and rhf76_set_data_rate to RHF76.h to allow set/query date rate config
5. added rhf76_at_cmd_exe for DEBUG purpose, so that user can execute any AT+ commands they want
6. added code in lora_demo.c to demonstrate package segmentation.
1. modified the HTS221: removed magic numbers, added a sensor_tempnhumi_t struct to accommodate temperature and humidity data
2. added .h and .c files for LIS3MDL magnetic sensor
3. added .h and .c files for LPS22HB pressure sensor
3. added IAR (EWARM) project for lorawan example
4. added bsp.c and bsp.h to manager the sensors
