Misc fixes:
- make an overload of Launch() that takes an init list of const char* if all you need to tweak in the launch info are the command-line arguments
- make Run() return an int that you can use as an exit-code
- make dynamic values work properly when recursing in FetchVariables()
- make the po output more obvious in verbose mode

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@178578 91177308-0d34-0410-b5e6-96231b3b80d8