Tango_OMemstream removed, string used instead

- Integration Mode available for DDC/SCPI devices
- tests done with a K617 (DDC) and a K6485 (SCPI)

- integration mode OK (tests done with K_486)

- TODO: DDC/SCPI
integration time for ScanServer compatibility.
report config for all DDC
add configuration in SCPI start command

- modif done on Novelec part :
bug fix