Fix Hashing bug and remove putobject string and list 1001 objects tests (#628)
Fix Hashing bug and remove putobject string and list 1001 objects tests (#628)

Removing putObject string buffer test as it is incorrect.
There are chances that some Unicode character can come into
play and the test might occasionally fail.

Fixed a Hash calculation bug in getpartialobject test, seen in Mint.
The code assumed that the first 100KB of data in the 6MB object will
have the same size as a 100KB object itself.

The listObjects test to list 1001 objects fails intermittently in
removeObject part of the test in Appveyor.
This will be tracked in a separate issue.

Fixes #627 and #629
minio/minio-js,krishnasrinivas/minio-js