Minor fixes.
Upgrading to newer version of cygwin1.dll
No longer using RSYNC for uploads to staging. Using "cat >>" instead.
Deleting this module, whose class hasn't been used since early
prototypes of MyData which required MyTardis administrator credentials.
Adding some additional Cygwin binaries. chgrp.exe is useful for
assigning a Cygwin group to a private key file, which is necessary
for asssigning permissions (with Cygwin's chmod.exe). cygpath.exe
is useful for converting DOS paths to Cygwin paths, e.g.
/cygdrive/C/Windows/
Adding new data models, which are used when an unverified
datafile record is found, in which case the file probably needs
to be uploaded to staging, but we don't need to create a datafile
record, because one already exists.  DataFileModel is used in
FoldersController.py
MyData users need to be able to write to the etc and .ssh
directories within MyData's minimal Cygwin installation.
etc is for /etc/group and .ssh is for .ssh/known_hosts in cases
where the Cygwin ssh binary fails to use the users' non-Cygwin
home directory for their Cygwin home directory.
Now refuses to run from Cygwin or MSYS environment.
The datafile JSON from the MyTardis API only includes the resource
URI for the dataset, not the JSON, so we pass in a MyData
DatasetModel object to associate with the DataFileModel object.
Recording instrument in newly created dataset records and
improving exception handling.
Removed unused function.
Some new Exception classes to help with managing
common HTTP error codes returned by MyTardis's API.
Improving exception handling.
Removing 'Record' where it is redundant.
New method for checking each datafile's created date/time
to record in each new datafile's JSON when POSTing to the
MyTardis API.  This is used by MyTardis's new facility view.
Also now sorting datafiles which affects order of uploads.
Order is still non-deterministic when running multiple
upload threads (the default for the SSH upload method).
Removing 'Record' where it is redunant.
Improving exception handling, particularly for 401
unauthorized errors.
Removing 'Record' where it is redundant.
Added bytesUploaded attribute. Progress percentage could now be
calculated on the fly from bytesUploaded and from filesize, but
filesize is currently stored as a human-readable string and
progress bars are also used for MD5 sum calculations.
Cancel remaining uploads now leaves the failed uploads in the
Uploads view and only removes the uploads which were in progress
or not started when the cancel request was made.