Signature calculation has now moved out from being a package to
top-level as a layered mechanism.
In case of payload calculation with body, go-routines are initiated
to simultaneously write and calculate shasum. Errors are sent
over the writer so that the lower layer removes the temporary files
properly.
Fail createObject() if a file already exists and one attempts
to create a prefix/directory by same name.
Send an approriate error back to the client as 409 Conflict.
Remove option of providing Technique and handling errors based on that
choose a matrix type automatically based on number of data blocks.
INTEL recommends on using cauchy for consistent invertible matrices,
while vandermonde is faster we should default to cauchy for large
data blocks.
Harshavardhana