// any feature to be highlighted in the sequence, with optional fields related to this feature:
// - "start"/"stop" : positions on the clone sequence (starting at 1)
// - "delLeft/delRight" : a numerical value . It is the numbers of nucleotides deleted during the rearrangment. DelRight are compatible with V/5 and D/4 segments, delLeft is compatible with D/4 and J/3 segments.
// - "seq" : a sequence
// - "val" : a numerical value
// - "info" : a textual vlaue
//
// JUNCTION//CDR3 should be stored that way (in fields called "junction" of "cdr3"),
// its productivity must be stored in a boolean field called "productive".