MinidumpYAML: Add support for ModuleList stream

Summary:
This patch adds support for yaml (de)serialization of the minidump
ModuleList stream. It's a fairly straight forward-application of the
existing patterns to the ModuleList structures defined in previous
patches.

One thing, which may be interesting to call out explicitly is the
addition of "new" allocation functions to the helper BlobAllocator
class. The reason for this was, that there was an emerging pattern of a
need to allocate space for entities, which do not have a suitable
lifetime for use with the existing allocation functions. A typical
example of that was the "size" of various lists, which is only available
as a temporary returned by the .size() method of some container. For
these cases, one can use the new set of allocation functions, which
will take a temporary object, and store it in an allocator-managed
buffer until it is written to disk.

Reviewers: amccarth, jhenderson, clayborg, zturner

Subscribers: lldb-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60405

llvm-svn: 358672