Log Message: 
NKSP: Implemented common real number math functions.
* Added builtin real number functions "round()", "ceil()", "floor()",
"sqrt()", "log()", "log2()", "log10()", "exp()", "pow()", "sin()",
"cos()", "tan()", "asin()", "acos()", "atan()".
* Added builtin script real number constant "~NI_MATH_PI".
* Added builtin script real number constant "~NI_MATH_E".
* Added NKSP test cases for builtin functions "round()", "ceil()",
"floor()", "sqrt()", "log()", "log2()", "log10()", "exp()", "pow()",
"sin()", "cos()", "tan()", "asin()", "acos()", "atan()".
* Bumped version (2.1.1.svn14).
