DRTVWR-418: Fix a round of compile errors surfaced by -std=c++11.

These are mostly things that were in fact erroneous, but accepted by older
compilers.

This changeset has not yet been built with Visual Studio 2013 or Linux gcc,
even with -std=c++11.

This changeset has not been built *without* -std=c++11. It should be used in
conjunction with a corresponding change to LL_BUILD_DARWIN_BASE_SWITCHES in
viewer-build-variables/variables.

This is a work in progress. We do not assert that this changeset completes the
work needed to turn on -std=c++11, even on the Mac.