So that no need to explicitly specify <int64_t> or LL wrt int
literals, which dont need 64bit space by default.
Which also means one shouldnt/cant mix up type of value stored and
default type specified when getting.
Rename all the log messages to have GKV and not SC.
The log messages in get_vector made conditional to GKV_DEBUG, this
was missed out earlier in simpcfg itself.