3.0: Change all type names to lcb_TYPENAME rather than lcb_typename_t

The newer convention is done in most of the 2.4 codebase. Using this convention makes it easier to distinguish types inside source code and also allows the names to be more conformant to POSIX standards which technically prohibits the _t suffix from being used.

We can either remove the old names completely, or place them in deprecated.h.

Probably the most notable difference would be in the lcb_t – which would need to be renamed to something like lcb_pBUCKET