Refactor data objects for new clawdata

Includes refactoring of gauge data objects located in clawutil as well
Bug fix for misspelled attribute
Fix 1d plotting bugs
Remove extraneous exception handling
Add more colorbar attributes
Merge pull request #25 from mandli/new-data

Support for new Data Objects in Clawdata
Pass format through various routines so html plotting works with PETSc
output.
Merge pull request #26 from ketch/master

Pass format argument so that html plotting works with PETSc output files.