cpimport now has the ability to use libmarias3 to read an object from an
S3 bucket instead of a file on local disk.
This also moves libmarias3 to utils/libmarias3.
If the first byte of a char/varchar was > 0x80 then it will break the
min/max values for an extent during cpimport. This patch makes the
min/max compare unsigned and only switches to signed when storing.
In addition send all the LDI / INSERT...SELECT data to cpimport, not
truncated. Let cpimport figure out the truncation point.
cpimport would truncate UTF8 data half way through a character which
would cause problems for functions using that data. This patch
calculates the correct truncation point when inserting the data.
