Optimizations in vls to reduce the number of server calls

vls was making unnecessary calls to the server causing it to be considerable slower in certain situations.

Added --head flag to vcp and vcat

The 'head' flag allows for the retrieval of file header information only if the server supports it for a given file type.

vtag repair

Update restores ability of vtag to list all properties of a file.

Explicit dependency on enum34

vos=3.0.6

Update setup.cfg

Faster vls for large directories (unless wild cards are used)

Listing of a large directory is now significantly faster and can be piped to other applications (more, head, etc) or terminate. Sorting is performed on the server side.
This does not work when used with wild cards.

Globing support in vls

vos=3.0.4

Update setup.cfg

Fixed bug in vos.copy

vos.copy transferred identical files without checking the md5 first.
Also remove support for Python 3.3

vsync patch

vos=3.0.2

Update setup.cfg

Renamed the exceptions log file

vofs=3.0.1

Update setup.cfg

A working 'requests' based release

This release corrected some errors and bugs in the previous alpha release. This version passes the integration tests.