Ubuntu 18.04 uses GCC 7.3 which is a little stricter than before.
Fixes a few errors due to implicit includes that are no longer implicit
and a ton of warnings about the implied alignment of code in
utils/common/any.hpp
This fix improves the performance of ExeMgr by doing the following:
* Significantly reduces the amount of time the xml configuration is
scanned
* Uses a much faster way to determine the CPU core count
* Reduces the amount of times certain allocations are executed
* Rowgroup pre-allocates vectors for 1024 rows
This improves performance for the first query of a connection and the
performance for smaller result sets. It may well improve performance in
other areas too.
