reset_sdp.sh v4.0.0:
* Added config settings: ServerID, ServerType, TargetServerType
* Enhanced internal docs.
* Enhanced docs for '-local' flag.
* Added '-dapi' flag to install derived APIs (P4Perl/P4Python).
If this flag is used, failures to build P4Perl and/or P4Python
are reported as errors.
* Tweaked '-fast' to now mean "skip package installations," and
documented as such.