Imexam

--------------------------
- version upgraded needed for the release on pypi so it would accept the upload

------------------------

- Ginga viewer with matplotlib backend fully flushed out,
this uses an event driven examination which is activated by key-press

- general bug fixes

- documentation updates

---------------------------

- Ginga is added as an optional viewer

----------------------------
- Fixed bug where a user displayed array reference was not getting reset when a fits image was loaded into the frame instead

- added suggested changes from 2to3, and set use_2to3 to False

- restructured docs for astropy style and added more detailed example information

- general bugs fixed as they were found

- full imexam() support for arrays loaded from memory added

- restructured how the code tracks what is in the viewer. It used to track just the
current frame, now it keeps a dictionary of what's loaded into the viewer which also
contains some specifics about the data in each respective frame. This was necessary to
allow user display and tracking of arrays, but also is a nicer way to store the information
and give users access to more details about the viewer in general if they are scripting something
themselves.

- the logging method dropped a reference in one of the last commits, this was fixed and logging the
session to a file for reference should be functioning correctly again.

- fixed an internal tracking problem in cases where the user loaded files through the gui and then
immediately issued the imexam() command. The viewer information for the object had not been updated in
between because it waits for a call to the window before checking - I added this check to the top of
imexam function.

----------------------------

- zero-indexing bug fixed for data pixel display

- added support for x-D image cubes. They display, and are correctly tracked through
the imexam loop. Several new functions were added to support this.

- fixed the zoom(int) bug, you can supply an int or string to the zoom function and it will be happy

----------------------------

This update should address all of the issues that chanley raised,, including:

- Removing the remaining blind exceptions

- Removing unused imports

- Setting an appropriate default value for the connect.current_frame

- the code now calls to the active window to set the frame

- I also updated related ds9 module frame method to set the frame to a decent default if not set

- the astropy.io.fits import was simplified

- In addition, some minor typos and bugs were fixed that appeared when making these updates.