<rdar://problem/12820334>

I modified the "Args::StringtoAddress(...)" function to be able to evaluate address expressions. This is now used for any command line arguments or options that takes addresses like:

memory read <addr> [<end-addr>]
memory write <addr>
breakpoint set --address <addr>
disassemble --start-address <addr> --end-address <addr>

It calls the expression parser to evaluate the address expression and will also work around the issue where the compiler doesn't like to add offsets to function pointers (which is what happens when you try to evaluate "main + 12"). So there is a temp fix in the Args::StringtoAddress() to work around this until we can get special compiler support for debug expressions with function pointers.

llvm-svn: 169556