Add IRC metadata and update repository and bugtracker URLs

Shadowgit is still the canonical repo, but advertise the github mirror
for ease of contribution.
Update help/support and contributing POD section

Mostly stolen from DBIx::Class
Fix JSON and YAML tests if the defaults have been tweaked (RT#98824)

Some people tweak their JSON (or YAML) modules to format things
differently by default, so roundtrip the expected data through a
load/dump to make sure it's formatted thes same.
Switch back to upstream Travis helpers
Install YAML and XML::LibXML before build-dist

They are required when running Makefile.PL in author mode.
Install YAML and XML::LibXML in the perl used for testing too

The perl used for build-dist is not necessearily the same as the one
we're testing under.
Switch back to my travis helpers fork

It should pick up the configure-deps itself now.
Factor out quote option handling
Clean up option parsing and identifier quoting in Producer::PostgreSQL

Remove the unused quote_field_names and table_name options and use the
factored-out quote option parsing function.
Clean up option parsing and fix identifier quoting in Producer::MySQL
Fix handling of quoted identifiers and strings in Parser::SQLite
Fix handling of quoted identifiers and strings in Parser::MySQL
Fix handling of quoted identifiers and strings in Parser::PostgreSQL
Fix handling of quoted identifiers and strings in Parser::SQLServer
Fix handling of quoted identifiers and strings in Parser::Oracle
Escape the closing quote character when quoting indentifiers
Test table and field names with quote characters in them
Escape quotes in string values in producers
Test round-tripping default values with quotes and backslashes
Test round-tripping decimal default values