Pycounter

* COUNTER 3 support removed (was at EOL in 2014).
* CounterReport no longer has .year attribute (doesn't make sense for part or multi
year reports, and wasn't on COUNTER 5 reports in pycounter 2.0)
* Dropped support for python 2 and 3.5. Now supports only python 3.6+

* add support for COUNTER 4 title-level turnaways reports (JR2 and BR3).

* COUNTER 5 support (still a work in progress; see README).
* Drops support for python 3.4, which is at its end of life.
* Deprecates parsing of COUNTER 3 reports (which should not have been issued after
January 2014)

Bugfixes
* SUSHI: Deal with missing institutional identifier for customer. [Geoffrey Spear]

(see Issue 72. This should catch the exception involved in the
issue, but there may be a wider issue with the Gale report since
the "customer" object involved should not be None if there's
an actual report to read, since the report itself is in the
Customer XML element.)


Code quality/CI

* Add pre-commit black hook, format all code with black. [Geoffrey Spear]

* Python 3.7 support. [Geoffrey Spear]

* Replace arrow library with pendulum. [Geoffrey Spear]

* Pyup: try updating all deps. [Geoffrey Spear]

Other

* SUSHI: Verify SSL certs by default. [Geoffrey Spear]

(Bumps version to 1.1 because this could be a breaking change for
sites that rely on requests to broken servers working without a flag)

Fixes 67

* Don't try to do string formatting on given output file name. [Geoffrey Spear]

Fixes 58

Bugfixes

* Negate bash regex match correctly. [Geoffrey Spear]

Issue 63

* Retry SUSHI reports if "Report Queued" message is returned. [Geoffrey Spear]

(This is kind of an ugly hack that looks for this string in the
raw XML. A nicer fix will be possible with a fix for 3 )

Docs
* Help for sushiclient --nodelay option (which probably shouldn't actually be used, but was helpful for testing without making the rest suite wait 60 seconds) [Geoffrey Spear]


Code quality/CI

* Exclude builds for flake8/lint/manifest? [Geoffrey Spear]
Issue 63

* Only use pylint version 1. [Geoffrey Spear]

(version 2 drops py2 support)