New assertion "assert.isXXX()", a syntax sugar of "assert.isInstanceOf()"

[piroor]

Now, assert.isInstanceOf() requires two arguments (the expected type and the actual object), but other "isXXX" assertions (isString(), isArray(), etc.) requires only one argument, the actual value. It is annoying. We need "assert.isNSIFile()" (or "assert.is_nsIFile()") and other assertions like "isString()".

By "noSuchMethod()", we can generate such assertions automatically. "assert.isNSIFile()" should work as "assert.isInstanceOf(Ci.nsIFile, ...)".