Missing simple RX application features

[roland-sipos]

List of features to be implemented for the simple RX receiver (fdaq equivalent):

[gkokkoro]

• The universal stream id (det + crate + slot +strm) works but it’s indecipherable - need something more structured
• Detailed per-stream stats are essential (seq_id jumps, unexpected_packet size, etc)
• The number of lookup maps should be minimised (now there are 3) to avoid unnecessary lookups - worth looking into having a single map with a struct as value (stuct holding all the counters per stream)
• Too much using namespace …
• The m_buf->data_len does include ethernet and udp header (+1 mysterious byte I haven’t managed to understand). The length of those headers needs to be subtracted before comparison