Throw an exception if a negative time delta is passed to World.step.
tree6549371a26aded253015ddc54b7b420dbf2e8de1
-rw-r--r-- 16 .gitignore
-rw-r--r-- 11358 LICENSE
-rw-r--r-- 216 NOTICE
-rw-r--r-- 509 README
-rw-r--r-- 3319 build.xml
-rw-r--r-- 82 manifest.mf
drwxr-xr-x - nbproject
drwxr-xr-x - src
drwxr-xr-x - test