Changed catch(std::out_of_range) to catch(std::out_of_range &) in order to avoid the following type of compilation error:

../CTA/common/checksum/ChecksumBlob.hpp:145:18: error: catching polymorphic type ‘class std::out_of_range’ by value [-Werror=catch-value=]
     } catch(std::out_of_range) {
                  ^~~~~~~~~~~~
cc1plus: all warnings being treated as errors

If CHECKSUM_BLOB is NULL, the code will fall back on CHECKSUM_ADLER32.

Sets the ChecksumBlob from the supplied protocol buffer, unless the
protobuf is invalid, in which case it uses the supplied Adler32 checksum
instead.

- Removes assumption that if we have a valid checksumBlob it must
  contain an ADLER32 checksum. (Some of the unit tests have MD5
  checksums only).

- Removes assumption that if we have a valid checksumBlob it must
  contain an ADLER32 checksum. (Some of the unit tests have MD5
  checksums only).

Mostly changes to new unit tests.

It isn't necessary to serialize the protobuf to compute the serialized
length, use ByteSizeLong() instead.

Adds support for byte array columns in the DB. Implementation done for
SQLite, the others are placeholders.

The blob is a set of type/value pairs which can be serialised to a byte
array for storage in the DB.

Mostly changes to new unit tests.

It isn't necessary to serialize the protobuf to compute the serialized
length, use ByteSizeLong() instead.

Adds support for byte array columns in the DB. Implementation done for
SQLite, the others are placeholders.

The blob is a set of type/value pairs which can be serialised to a byte
array for storage in the DB.