Skip multi-line comments in findClose() and findCommaOrEnd()

An example of a fixed bug follows. For the macro
    #define m( /*a)b*/ x )x
- before this commit the tooltip contained:
    Function macro: m(/*a)
    Body: b*/ x )x
- at this commit the tooltip contains:
    Function macro: m(/*a)b*/ x)
    Body: x