tests/float/: Skip tests if "math" module is not available.

tests/float/math-fun-bool.py

 # Test the bool functions from math
 
-from math import isfinite, isnan, isinf
+try:
+    from math import isfinite, isnan, isinf
+except ImportError:
+    print("SKIP")
+    import sys
+    sys.exit()
 
 test_values = [1, 0, -1, 1.0, 0.0, -1.0, float('NaN'), float('Inf'), 
                -float('NaN'), -float('Inf')]

tests/float/math-fun.py

 # Tests the functions imported from math
 
-from math import *
+try:
+    from math import *
+except ImportError:
+    print("SKIP")
+    import sys
+    sys.exit()
 
 test_values = [-100., -1.23456, -1, -0.5, 0.0, 0.5, 1.23456, 100.]
 p_test_values = [0.1, 0.5, 1.23456]