Update the installation instructions in the tutorial to be more specific about the Lua versions used by the various available packages, and to include some troubleshooting advice.

I decided to go back to semantic versioning with this release, so this has
become version 0.10.1 now. Incidentally, this numbering also works better in
the meta patch. While I was at it, I also fixed the garbled formatting of the
meta patch.

Note that this version is still backward-compatible with versions 0.8 and 0.9,
so existing Pd-Lua scripts from older versions should continue to work. There
are no user-visible changes in pdlua, apart from the support for Lua 5.4 which
was added already in version 0.10.

0.10.1 adds the pd-lua-intro tutorial, which also includes improved
live-coding support through an add-on Lua module in tutorial/examples/pdx.lua,
as well as the accompanying pdlua-remote.pd abstraction and the
pdlua-remote.el elisp file in the same folder, as explained in the
tutorial. These items aren't currently installed anywhere, so you may want to
copy those bits and pieces to your extra/pdlua folder for system-wide
installation.

document DESTDIR instead of broken DESTROOT

Streamline the Windows/mingw build rule to simplify in-tree builds where pd.dll may be in a different subdirectory of .

nw.js (Pd-l2ork 2.x) support: opening the Lua script file in Purr Data now does the right thing on Windows, too

macOS compilation: Pd-extended is getting a bit long in the tooth, let's assume a vanilla install instead