Added a troubleshooting page as a place to add commonly asked questions with solutions. 

The first two questions I have added explanations and answers to are:
- File and line breakpoints are not getting hit
- How do I check if I have debug symbols?



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@184159 91177308-0d34-0410-b5e6-96231b3b80d8