ABI compatibility broken on 2.3 when using config cache.

"Compat" structure which is used when creating a config cache are not ABI compatible between 2.3 and older versions.

Details:
"lcb_compat_st" structure embeds an "lcb_create_st" structure in its first field. second field. The lcb_create_st" structure has increased in size in 2.3, it now includes a transport selection and a memcached host array.

Work arounds:

For C/C++ code using LCB a recompile will be required or if compatibility is required across 2.2 and 2.3 do not use the configcache.

From the SDKs (ruby, python and php) that sits on top of LCB if you wish to use the config cach the SDK will need to be reinstalled after LCB 2.3.0 has been installed.