o TestEvents.py:

Add a usage example of SBEvent APIs.

o SBEvent.h and SBListener.h:

Add method docstrings for SBEvent.h and SBListener.h, and example usage of SBEvent into
the class docstring of SBEvent.

o lldb.swig:

Add typemap for SBEvent::SBEvent (uint32_t event, const char *cstr, uint32_t cstr_len)
so that we can use, in Python, obj2 = lldb.SBEvent(0, "abc") to create an SBEvent.

llvm-svn: 134766