* python.d/dnsdist.chart.py PEP 8 cleanup
* Converted tabs in indentation to spaces (this is why the diff looks
huge).
* Fixed container literal formatting.
* General cleanup regarding blank lines.
* python.d/dns_query_time.chart.py PEP 8 cleanup
Fixed container literal formatting.
* python.d/dockerd.chart.py PEP 8 cleanup
Fixed overly long lines and trailing empty line.
* python.d/dovecot.chart.py PEP 8 cleanup
Made string literals use consistent quoting and fixed container literal
formatting.
* python.d/elasticsearch.chart.py PEP 8 cleanup
Fixed container literal formatting.
* python.d/exim.chart.py PEP 8 cleanup
Fixed string quoting and container literal formatting.
* python.d/fail2ban.chart.py PEP 8 cleanup
Fixed string quoting and container literal formatting.
* python.d/freeradius.chart.py PEP 8 cleanup
Fixed quoting of strings and formatting of container literals.
* python.d/go_expvar.chart.py PEP 8 cleanup
Fixed formatting of conainer literals.
* python.d/haproxy.chart.py PEP 8 cleanup
Make string quoting consistent and fix formatting of container literals.
* python.d/httpcheck.chart.py PEP 8 cleanup
Fixed quoting of strings and formatting of container literals.
* Fix syntax issue in httpcheck module caused by previous commit.
