Install: Fix install on Linux to not take 10+ minutes

[davidfstr]

Problem

• The current instructions for installing Crystal on Linux rely on "pipx install".
• "pipx install" of Crystal on Linux takes 10+ minutes because wxPython must be compiled from source.
• It takes so long because there are no pre-compiled wxPython wheels for Linux.
• There are no pre-compiled wxPython wheels for Linux because historically it has been difficult to compile a manylinux wheel of wxPython.

In an era with instant app installs from app stores, it's unreasonable to expect users to be patient for 10+ minutes to install an unproven app.

Solution

• Choose 1 of:
  • [#] Alter Linux install instructions to use a .wagon to install wxPython, for popular Linux distributions Not any easier that just building a binary, because .wagon must depend on major Python and GTK versions, which have too many varying combinations.
  • [#] Build a manylinux wheel of wxPython Infeasible (i.e. too hard)
    • Last attempt was in Aug 2022 on this thread, this PR, and this set of wheel files
    • wxPython's download page also mentions the last attempt to make a manylinux wheel:

      • Unfortunately, attempts to pound the wxPython peg into the manylinux1 hole have not been very successful. Maybe manylinux2 will be a better fit.

  • Build Linux binary (#161) 👈(do this)

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