SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
This allows the same code to be used to read into a std::string, which
allows for eliminating the vector->string transfer when reading the
manifest file.
A ContiguousContainer is a concept that includes std::array,
std::string, and std::vector.
Makes it way harder to introduce resource leaks, and plugs the existing
resource leaks in the constructor and Install() where the file wouldn't
be closed in some error cases.
Pierre Bourdon