add option "-fr5" into Readme.txt

                      EVS RTP Payload Format. The SDP parameter hf_only is required.

                      Reading RFC4867 AMR/AMR-WB RTP payload format is not supported.

-Tracefile TF       : VoIP mode: Generate trace file named TF

-fr5                : option to perform rendering + head-tracking with 5ms frame size

-fec_cfg_file       : Optimal channel aware configuration computed by the JBM

                      as described in Section 6.3.1 of TS26.448. The output is

                      written into a .txt file. Each line contains the FER indicator

-dpid ID            : Directivity pattern ID(s) (space-separated list of up to 4 numbers can be 

                      specified) for binaural output configuration

-aeid ID            : Acoustic environment ID (number >= 0) for BINAURAL_ROOM_REVERB output config.

-fr5                : render audio with 5 ms framing

-smd                : Metadata Synchronization Delay in ms, Default is 0. Quantized by 5ms subframes.

-level level        : Complexity level, level = (1, 2, 3), will be defined after characterisation.

                      Currently, all values default to level 3 (full functionality).