Merge pull request #109 from jvdp1/combi

Addition of a default flag --markdown

modify CI action

Fix issue#82 Help/Version message missing

Fix issue#82 Help/Version message missing: re-add check on negative
error flags to catch help/version message invocation

v1.2.3 Fix a new bug in issue#82

Fix a new bug in issue#82. Fully backward compatible.

Fix bug in ignoring unknown clas

Add ignore passed unknown CLAs, fix issue#82

The CLI can now be initialized with a flag for ignoring the passed CLAs
that are unknown. An error is still echoed, but the CLI parsing goes on
until the end without exit the flow. By default a passed unknown CLA
raises a blocking error as in the previous verions.

This change addresses the need by:

add a new option to `init` method of CLI object, e.g.

call cli%init(..., ignore_unknown_clas=.true.)

A dedicated test has been added, i.e.
`src/test/flap_test_ignore_unknown_clas.f90`

Side effects:

Nothing.

Fully backward compatible.

Add bash completition script output issue#86

Add bash completition script output: given a CLI now it is possibile to
save a *bash auto completition script* that once *sourced* in a bash
shell provides the auto completition capabilities.

Note tha for CLI with multiple CLAs groups (like the `git` command) the
generated script is smart enough to distinguish the CLAs of each group,
e.g. the added test with 2 CLAs groups generates the following script:

```bash
_completion()
{
  cur=${COMP_WORDS[COMP_CWORD]}
  prev=${COMP_WORDS[COMP_CWORD - 1]}
  if [ "$prev" == "compile" ] ; then
    COMPREPLY=( $( compgen -W "  --compiler -c --flags -f --help -h --version -v" -- $cur ) )
  elif [ "$prev" == "clean" ] ; then
    COMPREPLY=( $( compgen -W " --clean -c --clean-all -ca --help -h --version -v" -- $cur ) )
  else
    COMPREPLY=( $( compgen -W " --help -h --version -v compile clean" -- $cur ) )
  fi
  return 0
}
complete -F _completion flap_test_save_bash_completition
```

Fix duplicated passed CLAs bug issue#85

Fix the bug regarding duplicated passed CLAs: if the multiple instances
of the same non positional CLA is passed to the CLI an error is raised.

Add first support for ANSI color/style

Stable release, fully backward compatible.

Fix bug #71

Stable release, fully backward compatible.