MCA status bar

Remove all items from the Chromatogram Alignment Editor status bar, except the following info:

• "Ln K/N"
  If a character is selected in the Reads Area or a single read is selected in the Reads Name List Area, K is the numerical order of the read. Otherwise, K should be equal to "–".
  N is the number of reads. Make sure it is updated when a read is deleted.
• "RefPos M/L"
  If a character is selected in the Reads Area, M is the numerical order of the column in the reference (gaps are not taken into account). Otherwise, M is "–".
  L is the number of characters in the reference (gaps are not taken into account).
• "ReadPos RM/RL"
  If a character is selected in the Reads Area, RM is the numerical order of the character in the read (gaps are not taken into account). Otherwise, RM is "–".
  If a single read is selected, RL is the number of characters in the read. Otherwise, when several reads are selected or there is no reads selected, RL is "–".