Add `pgagent_jobs` test.

From: "David E. Wheeler" <david@justatheory.com>

This patch adds support for checking for failed pgAgent jobs within a specified
period of time. You can specify either --critical or --warning as a period of
time, and it will report on failures within that period of time previous to the
current time. Job failures are determined by a non-0 status in a job step
record.

Using this test obviously requiers that the pgAgent schema be installed. I've
also included a bunch of unit tests to make sure it works the way I would expect
(the test will create a schema for testing) and documentation.

As part of this, I've introduced the `any_warning` argument to
`validate_range()`. The `pgagent_jobs` test does not care if you specify a
warning value greater than the critical value (indeed, I expect that if one used
both at all, the warning would be much longer). So this new argument prevents
the `range-warnbigtime` or `range-warnbigsize` failures from being triggered.

Cedric: I sorted the POD and added the action_info so that t/05_docs.t is ok.
I also built and push the new .html
Minor change in bloat test

The test was loading Data::Dumepr but not using it.
Update History for 2.20.0

Add check for pgagent jobs (David E. Wheeler)
Note the symlink for generic tarball
Revert "Minor change in bloat test"

This reverts commit 7788d081ab5ed74d53f699bc7333e00f2bb59d9a.

GSM: Data::Dumper is handy for when you do want to Dump something.
Fix the createlang during init

There was a copy-n-paste error, only affecting < 8.1 .
Allows PGBINDIR in check_postgresrc

This is the same approach as it is with PSQL variable (the $NO_PSQL_OPTION
variable har-coded *MUST* be set to 0 to use them).

PGBINDIR can be set in ENV, hard-coded in check_postgres.pl or set via
command-line argument.
PGCONTROLDATA and PSQL can still be used but should be deprecated.

the logic is if NO_PSQL_OPTION=1 :
 * that PGBINDIR can be set via environment variable, but not via config
file or command-line argument.
 * that PSQL can not be set explicitly, but derived from PGBINDIR
Fix repository entry in META.yml

just a trailling / and a s/https/git/ change
Update the french translation
Make sure STDOUT is using utf8. Per report from Emmanuel Lesouef
Merge branch 'master' of bucardo.org:/var/lib/git/check_postgres
Note recent change
Allow spaces within items within same_schema action.
Bump version to 2.20.0
Fix French UTF-8 character.
Cleaner "ERROR" output
Better detection of stats_command_string being off.
Start work to allow txn_idle on old systems.
Allow txn_idle to work again for < 8.3 servers by switching to query_time.
Fix check_postgres_hitratio documentation

check_postgres_hitratio was wrong called
check_postgres_database_hitratio in the documentation.
Remove odd whitespace junk.
Merge branch 'master' of bucardo.org:/var/lib/git/check_postgres