Update Brackets.java

Fixed bug first spotted at http://code.google.com/p/processing/issues/detail?id=1032 where brackets aren't seen directly after a slash.
An example that failed:
min(1, x/(1.0));
min(1, x /(1.0));
Merge pull request #2313 from GKFX/patch-3

Backtrack after / so that it's not skipped on bracket handling