Update tutorials

Complete update of all the SCIFIO tutorials.

Focused on making the tutorials more straightforward - avoiding
unnecessary code or poor API usage (even if intentioal for illustration
purposes). This should greatly improve the capacity for copying and
pasting the code from these tutorials, to make them more useful for
beginning SCIFIO developers.

Tutorials were removed/added as appropriate to keep with these new
goals.

Documentation was updated heavily for both meaning and to be accurate
for the current SCIFIO API, as many statements were outdated.

Closes issue 10 in the SCIFIO trac.
Removed ome/SCIFIOTutorial.png

These png samples are generated as part of the tutorials. No reason to
commit them.