lang/python27, lang/python35, lang/python36: libressl 2.7 compatibility

[vishwin]

Summary

See PR 226883. Upon libressl releasing 2.7.1, upstream released their patches.

Test Plan

testport succeeds with ssl=base and ssl=libressl-devel. Fails otherwise, at least on my machine.

[mat]

No patch for 3.4?

[vishwin]

3.4 isn't affected by this last time I tested. In fact, upstream only patched 2.7, 3.6, 3.7beta and master; I manually backported the 3.6 patch to 3.5.

Also, my build failures seem to come from using ccache a wee bit much. These patches actually all work.

Should PORTREVISION be bumped for these?

[mat]

Bumping PORTREVISION is required when the port needs to be rebuilt because whatever was built has been updated. In this case, nothing builds, as far as I understand, so no.

[brnrd]

Works fine for me for weeks now

[koobs]

LGTM/Approved if this passes QA on all versions/archs (10,11,i386,amd64 explicitly, at least) eluded to in Issue 226883 Comment 3 and for all values of USES=ssl

Approved by: python (koobs)

[brnrd]

Python	SSL provider	11.1 amd64	11.1 i386	10.4 amd64	10.4 i386
Python 2.7.14_1	1.0.2k/1.0.1u (base)	log	log	log	log
Python 2.7.14_1	LibreSSL 2.6.4_1	log	log	log	log
Python 2.7.14_1	LibreSSL 2.7.2	log	log	log	log
Python 2.7.14_1	OpenSSL 1.0.2o_2,1	log	log	log	log
Python 2.7.14_1	OpenSSL 1.1.0h_1	log	log	log	log
Python 2.7.14_1	OpenSSL 1.1.1p5	log	log	log	log
Python 3.5.5	1.0.2k/1.0.1u (base)	log	log	log	log
Python 3.5.5	LibreSSL 2.6.4_1	log	log	log	log
Python 3.5.5	LibreSSL 2.7.2	log	log	log	log
Python 3.5.5	OpenSSL 1.0.2o_2,1	log	log	log	log
Python 3.5.5	OpenSSL 1.1.0h_1	log	log	log	log
Python 3.6.5	1.0.2k/1.0.1u (base)	log	log	log	log
Python 3.6.5	LibreSSL 2.6.4_1	log	log	log	log
Python 3.6.5	LibreSSL 2.7.2	log	log	log	log
Python 3.6.5	OpenSSL 1.0.2o_2,1	log	log	log	log
Python 3.6.5	OpenSSL 1.1.0h_1	log	log	log	log
Python 3.6.5	OpenSSL 1.1.1p5	log	log	log	log