Adding new Python API function to check for stopped threads.

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@179577 91177308-0d34-0410-b5e6-96231b3b80d8
New CallNext action for the test case that causes the next action in the sequence to be called right away

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@179578 91177308-0d34-0410-b5e6-96231b3b80d8