Commits
Andris Zeila authored 5543f8dfb26
........S. [ZBXNEXT-4002] refactoring: 1) moved history related stuff to a new library - zbxhistory 2) moved valuecache.h header back to the libs/zbxdbcache 3) moved public zbx_history_record_t functionality from valuecache to the zbxhistory library/headers 4) refactored valuecahe to use zbxhistory library to store/retrieve item values 5) refactored history storage code to support more than 2 storage backends