Removed maxmx and maxmy from calling sequences in 2d code

Arrays are dynamically allocated now so we don't need to pass these around.
Many changes -- see amrclaw/dev/fix_maxmx.txt for some comments on what was done.

Someone should test that examples work.  They have been converted too in examples/ directory

clawpack/apps codes that use amrclaw are not yet converted (only shockbubble?)

Removed tests/swirl directory which was out of date.
Moved sample regression test codes to dev/tests for now.