Improve install.sh's opening header:
Improve install.sh's opening header:

Direct end users to use package management if feasible.
Direct advanced developers to use CMake.
Redraw dependency tree lines without special characters.
Instruct users to use --yes-to-all for interactive builds.
Recommend --help to see installation options.

sourceryinstitute/opencoarrays,sourceryinstitute/opencoarrays,sourceryinstitute/opencoarrays