Further enhancements for the tools for collecting crash artefacts

As was proposed by @Totktonada in his review, I made a list for the required follow-up activity related to both tarabrt.sh and gdb.sh introduced in scope of tarantool/tarantool#5569. Major changes relate to the case when debug info is stripped from the Tarantool binary (e.g. in CentOS 8 binary packages until tarantool/tarantool#4611 is resolved). The following enhancements should to be done for the tools:

• Provide long alternatives for the existing options (e.g. -h / --help)
• Warn gdb.sh user whether Tarantool binary is stripped
• Provide an instruction how to enable the ELF with debug symbols, so it can be loaded by gdb.sh automatically
• Provide an URL from where debuginfo package may be downloaded and give advice how to unpack it (in gdb.shoutput, when we see the stripped executable)

  Examples:

  $ curl -LfsS https://download.tarantool.org/tarantool/release/2.8/el/8/x86_64/Packages/tarantool-debuginfo-2.8.0.0-1.el8.x86_64.rpm > tarantool-debuginfo-2.8.0.0-1.el8.x86_64.rpm
  $ mkdir tarantool-debuginfo-2.8.0.0-1.el8.x86_64.rpm.unpack
  $ cd tarantool-debuginfo-2.8.0.0-1.el8.x86_64.rpm.unpack
  $ rpm2cpio ../tarantool-debuginfo-2.8.0.0-1.el8.x86_64.rpm | cpio -idmv
  ./usr/lib/debug
  ./usr/lib/debug/.build-id
  ./usr/lib/debug/.build-id/a3
  ./usr/lib/debug/.build-id/a3/ad84db98a9b14e70d2915271904ddfe26b5f60
  ./usr/lib/debug/.build-id/a3/ad84db98a9b14e70d2915271904ddfe26b5f60.debug
  ./usr/lib/debug/usr
  ./usr/lib/debug/usr/bin
  ./usr/lib/debug/usr/bin/tarantool-2.8.0.0-1.el8.x86_64.debug
  64743 blocks
  (All are symlinks except tarantool-2.8.0.0-1.el8.x86_64.debug.)
  $ file usr/lib/debug/usr/bin/tarantool-2.8.0.0-1.el8.x86_64.debug
  usr/lib/debug/usr/bin/tarantool-2.8.0.0-1.el8.x86_64.debug: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter \004, for GNU/Linux 3.2.0, BuildID[sha1]=a3ad84db98a9b14e70d2915271904ddfe26b5f60, with debug_info, not stripped, too many notes (256)

Start by reading tools/tarabrt.sh and tools/gdb.sh, then review the linked proposal and existing option handling and stripped-binary behavior. Done means implementing the listed long options, stripped-binary warning, debug-symbol guidance, and debuginfo download and unpack instructions in gdb.sh output.