Refactoring Operations public API, SZ and ZFP tests
Created by: williamfgc
Operations in ADIOS, Variable and IO objects Removed public glue code for Operators. Removed examples and tests. Operations should run internally. Setting BP3 with external operators objects. Initial support and tests for SZ and Zfp in BP3 buffer Adding zstd dependency in FindSZ for latest SZ Internal API for BP3 Serializer and Deserializer defined Rebased master and resolved conflicts
TO DO:
add more tests add mgard