license: update text

docs: use @return instead of @returns

mesh: use MESH_PDU_TYPE_SEGMENT_ACKNOWLEDGMENT for outgoing seg ack messages

mesh: add mesh_network_notify_on_freed_pdu

mesh: remove transmic_len from mesh_access_pdu_t

mesh: replace ack and incomplete timer active uint8_t with bits in mesh_segmented->flags

mesh: use seq & 0x1fff instead of storing seq_zero explicitly in mesh_segmented_pdu

mesh: use MESH_TRANSPORT_FLAG_TRANSMIC_64 to store transmic_len in mesh_upper_transport_pdu

mesh: use MESH_TRANSPORT_FLAG_TRANSMIC_64 to store transmic_len in mesh_segmented_pdu

mesh: store lower transport retry count in mesh_segment_pdu_t

mesh: track alloc error in message builder finalize

mesh: use mesh_upper_transport_pdu_t for all access messages, remove mesh_transport_pdu_t

mesh: replace network_header in mesh_segmented_pdu by individual fields

mesh: replace network_header in mesh_control_pdu_t by individual fields

mesh: replace network_header in mesh_access_pdu_t by individual fields

mesh: remove mesh_unsegmented_pdu_t

mesh: use only segments in mesh_upper_transport_pdu_t, use mesh_upper_transport_pdu for unsegmented access

mesh: use mesh_upper_transport_pdu_t for segmented access message

mesh: define upper-(un)segmented-access/control pdu types, replace network_header in mesh_upper_transport_pdu_t

mesh: define mesh_upper_transport_pdu for (un)segmented access messages and segmented control messages

mesh: define mesh_control_pdu, flatten segmented control message into mesh_control_pdu in upper transport

mesh: remove mesh_transport_pdu_t from lower and upper transport

mesh: remove mesh_upper_transport_set_higher_layer_handler, deliver pdu sent via corresponding access/control handlers

mesh: free outgoing_segmented_pdu on test reset, remove dummy field from mesh_transport_pdu_t

mesh: mesh_message_pdu -> mesh_segmented_pdu