Pin stripe library

[martinvol]

What's this PR do?

Any background context you want to provide?

The stripe version should be updated with every release.

What ticket or issue # does this fix?

Closes #[issue number]

Definition of Done (check if considered and/or addressed):

• Are all backwards incompatible changes documented in this PR?
• Have all new dependencies been documented in this PR?
• Has the appropriate documentation been updated (if applicable)?
• Have you written tests to prove this change works (if applicable)?

[codecov]

Codecov Report

Merging #584 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #584   +/-   ##
=======================================
  Coverage   99.21%   99.21%           
=======================================
  Files          33       33           
  Lines        1911     1911           
  Branches      175      175           
=======================================
  Hits         1896     1896           
  Misses          7        7           
  Partials        8        8

Flag	Coverage Δ
#py27dj110	98.9% <ø> (ø)	⬆️
#py27dj111	98.9% <ø> (ø)	⬆️
#py27dj18	99.16% <ø> (ø)	⬆️
#py34dj110	98.9% <ø> (ø)	⬆️
#py34dj111	98.9% <ø> (ø)	⬆️
#py34dj18	99.16% <ø> (ø)	⬆️
#py34dj20	98.9% <ø> (ø)	⬆️
#py35dj110	98.9% <ø> (ø)	⬆️
#py35dj111	98.9% <ø> (ø)	⬆️
#py35dj18	99.16% <ø> (ø)	⬆️
#py35dj20	98.9% <ø> (ø)	⬆️
#py36dj111	98.9% <ø> (ø)	⬆️
#py36dj20	98.9% <ø> (ø)	⬆️
#py36dj20psql	98.9% <ø> (ø)	⬆️

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[blueyed]

I think this should rather use >=2,0,<3.0.