Added unit test using C99 INFINITY. This test actually tests a float
conversion bug where converting to float imposed overflow checking which
should not be there and causes this program to error out. This was seen
originally in Javascript, but it turns out Python has the same bug. Lua
does not have this bug. Other generators have not been tested.

This test also tests the rename feature. The Javascript generator was
not renaming the variable correctly.
Add `infinity` test-case to list of smoke tests.
Activate Javascript testcases `rename1-4`.