testenv/test/base_test.py: Add new variable SKIP_TEST
testenv/Test--https-crl.py: Use SKIP_TEST instead of magic number
testenv/Test--https.py: Same
testenv/Test-hsts.py: Same
testenv/Test-no_proxy-env.py: Same
testenv/Test-pinnedpubkey-der-https.py: Same
testenv/Test-pinnedpubkey-der-no-check-https.py: Same
testenv/Test-pinnedpubkey-hash-https.py: Same
testenv/Test-pinnedpubkey-hash-no-check-fail-https.py: Same
testenv/Test-pinnedpubkey-pem-fail-https.py: Same
testenv/Test-pinnedpubkey-pem-https.py: Same
* testenv/Makefile.am: Add new tests
* testenv/Test-pinnedpubkey-der-https.py: New test
* testenv/Test-pinnedpubkey-der-no-check-https.py: New Test
* testenv/Test-pinnedpubkey-hash-https.py: New test
* testenv/Test-pinnedpubkey-hash-no-check-fail-https.py: New test
* testenv/Test-pinnedpubkey-pem-fail-https.py: New test
* testenv/Test-pinnedpubkey-pem-https.py: New test
* testenv/certs/README: How to generate public keys with openssl tool
* testenv/certs/server-pubkey.der: New key file (DER format)
* testenv/certs/server-pubkey.pem: New key file (PEM format)