Updates for CUDA 11

See merge request !71

This relies on Linux/POSIX-specific functions, but it redirects the
underlying file descriptors instead of just the high-level C++ streams,
so that even output using the C stdio API are redirected. Most
importantly, this includes stack backtraces (from our StackBacktrace.h)
and any output from external libraries.

Replacing deprecated memory helpers

See merge request !70

Expression templates: unqualified calls to min/max functions in VerticalOperations.h

See merge request !69

Switched to unqualified calls to min/max functions in VerticalOperations.h to support argument-dependent lookup

Expression templates for nested vectors

Closes #60, #61, and #78

See merge request !68

Fixed VectorAssignmentWithOperation and changed types for VectorBinaryOperationsTest to cover operands with different types

Fixes #78

Fixes #60

Tests for vertical operations which are not well defined for nested
vectors are disabled.

Added OperandMemberType to avoid storing const-reference to temporary objects created in subexpressions