values or persistent expression variables. Now if an expression consists of
a value that is a child of a variable, or of a persistent variable only, we
will create a value object for it and make a ValueObjectConstResult from it to
freeze the value (for program variables only, not persistent variables) and
avoid running JITed code. For everything else we still parse up and JIT code
and run it in the inferior. 

There was also a lot of clean up in the expression code. I made the 
ClangExpressionVariables be stored in collections of shared pointers instead
of in collections of objects. This will help stop a lot of copy constructors on
these large objects and also cleans up the code considerably. The persistent
clang expression variables were moved over to the Target to ensure they persist
across process executions.

Added the ability for lldb_private::Target objects to evaluate expressions.
We want to evaluate expressions at the target level in case we aren't running
yet, or we have just completed running. We still want to be able to access the
persistent expression variables between runs, and also evaluate constant 
expressions. 

Added extra logging to the dynamic loader plug-in for MacOSX. ModuleList objects
can now dump their contents with the UUID, arch and full paths being logged with
appropriate prefix values.

Thread hardened the Communication class a bit by making the connection auto_ptr
member into a shared pointer member and then making a local copy of the shared
pointer in each method that uses it to make sure another thread can't nuke the
connection object while it is being used by another thread.

Added a new file to the lldb/test/load_unload test that causes the test a.out file
to link to the libd.dylib file all the time. This will allow us to test using
the DYLD_LIBRARY_PATH environment variable after moving libd.dylib somewhere else.

llvm-svn: 121745