Provide user feedback thu echo command

[qdelance]

This PR adds information in the output in case of "non OK" status (last command + last echo command if provided in the scenario)

Note that the way to use "echo" in scenario is documented in WAA on doc-dev (not yet on documentation.centreon.com)

Output:

# Nouvelle sonde, scenario OK, sans echo
 ./centreon_plugins.pl  --plugin=apps::selenium::plugin --mode=scenario --selenium-hostname=192.168.56.211 --selenium-port=4444 --directory=/var/lib/centreon_waa --scenario=scenario-local --warning=15 --critical=20
OK: 7/7 steps (6.775s) | 'time'=6.775s;0:15;0:20;0; 'steps'=7;;;0;7 'availability'=100%;;;0;100

# Nouvelle sonde, scenario KO, sans echo
 ./centreon_plugins.pl  --plugin=apps::selenium::plugin --mode=scenario --selenium-hostname=192.168.56.211 --selenium-port=4444 --directory=/var/lib/centreon_waa --scenario=scenario-local --warning=15 --critical=20
CRITICAL: 5/7 steps (6.816s) - clickAndWait link=Srvices  | 'time'=6.816s;0:15;0:20;0; 'steps'=5;;;0;7 'availability'=71%;;;0;100

# Nouvelle sonde, scenario OK, avec echo
./centreon_plugins.pl  --plugin=apps::selenium::plugin --mode=scenario --selenium-hostname=192.168.56.211 --selenium-port=4444 --directory=/var/lib/centreon_waa --scenario=scenario-local-avec-echo --warning=15 --critical=20
OK: 11/11 steps (13.092s) | 'time'=13.092s;0:15;0:20;0; 'steps'=11;;;0;11 'availability'=100%;;;0;100

# Nouvelle sonde, scenario KO



, avec echo
 ./centreon_plugins.pl  --plugin=apps::selenium::plugin --mode=scenario --selenium-hostname=192.168.56.211 --selenium-port=4444 --directory=/var/lib/centreon_waa --scenario=scenario-local-avec-echo --warning=15 --critical=20
CRITICAL: 8/11 steps (2.359s) - clickAndWait link=Srvices  - Ouverture services | 'time'=2.359s;0:15;0:20;0; 'steps'=8;;;0;11 'availability'=72%;;;0;100

Also remove a Perl warning if no scenario file is given as param.

[garnier-quentin]

First thanks. Two things. Prefer (= undef not needed):
my ($last_echo_msg, $last_cmd);

Second: Is it ok to display the echo even if it comes from X steps before ? You also need to care of "\n" or '|' in the echo.

[qdelance]

PR updated with:

• var declaration updated
• regexp applied on echo content