implement new features in SY525 fw 3.0

[delaere]

The main feature of the Version 3.00 of the SY527 software is the possibility of using non-homogeneous boards, i.e. boards containing different channel types. For example, the A933K board contains 2 channel types: 1 primary channel and 24 distributed channels.

The operation via H. S. CAENET changes slightly: in particular, the response to Code %3, %N is different than what described for non-homogeneous boards.

-> modification of the discoverBoards() method

• create several copies of a given board, and store the subindex in the last bytes.
• add the channel list to the board class (bit mask?)
• properly assign channels to the (sub)board object in the constructor
• adapt the getBoard method to hide the (index, type) encoding

[delaere]

I cannot test with heterogeneous boards (that I don't have) but with commit 91addfbdd1c92bd242dbf8009148412f378fbc48 fixing the last issue, this works for homogeneous boards and should be compatible.