We've had a mixture of the warnings pragma, the -w switch on the shebang
line, and no warnings at all. This patch removes the -w swicth and add
the warnings pragma to all perl sources missing it. It raises the
severity of the TestingAndDebugging::RequireUseWarnings perlcritic
policy to level 5, so that we catch any future violations.
Discussion: https://postgr.es/m/20200412074245.GB623763@rfd.leadboat.com
This makes it easier to do a web search for details of the policy that's
been violated, as well as displaying the name that might be needed for a
policy override.
Various perlcritic settings changes are being discussed, but this one
should be uncontroversial.
The .git directory might contain perl files, as hooks, for example.
Since we have no control over these they should be excluded from things
like our perlcritic checks.
Per offline report from Mike Blackwell.
Also add a function that centralizes the logic for locating all our perl
files and use it in pgperlcritic and pgperltidy as well as the new
pgperlcheck.
