PRoot v5.0.0

[Cédric VINCENT]

Hi all!

We are pleased to announce PRoot *v5.0.0* (http://proot.me/#downloads).

In a couple of words, this version uses its own program loader (ELF)
instead of the one shipped in Glibc.  That means a lot of bugs were
fixed, and it is now possible to proot into systems that don't provide
an ELF loader, like Android.  More details below:

Highlight
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PRoot used to rely on the ELF loader embedded in the ELF interpreter
from the GNU libc.  Sadly this latter suffers from many issues:

+ programs that use constructors or destructors might crash: a typical
  example is C++ programs.

+ programs that rely on the "rpath" mechanism and that are invoked
  through a symlink might not start: a typical example is the JVM on
  Debian.

+ programs that read processes command-line migth be confused because
  initial argv[0] is replaced: typical examples are ps and top.

Moreover not all ELF interpreters provide this feature.  For instance,
ELF interpreters shipped with Bionic (Android) and some versions of
the uClibC can't be used as ELF loaders.  As a consequence it was not
possible to proot into a rootfs that uses such C library.

Now PRoot has its own loader, that means all the limitations above
doesn't exist anymore.

Fixes
-----

+ Most bugs related to shebang support -- ie. "#!" at the beginning of
  a program -- were fixed.

Command-line interface changes
------------------------------

+ PRoot now starts a login shell when no command is specified; this
  makes the shell read profile files from the guest rootfs, as
  expected by some guest programs.  To get the old behavior, launch
  "/bin/sh" explicitly:

      proot -r whatever /bin/sh

+ The -R option now binds "/run" and "/var/run/dbus/system_bus_socket"
  too.  This is useful for guest programs that need to communicate
  with host services.