SSL: Add an option to disable certificate revocation checks

New tool option --ssl-no-revoke.
New value CURLSSLOPT_NO_REVOKE for CURLOPT_SSL_OPTIONS.

Currently this option applies only to WinSSL where we have automatic
certificate revocation checking by default. According to the
ssl-compared chart there are other backends that have automatic checking
(NSS, wolfSSL and DarwinSSL) so we could possibly accommodate them at
some later point.

Bug: https://github.com/bagder/curl/issues/264
Reported-by: zenden2k <zenden2k@gmail.com>

tests/data/Makefile.inc

@@ -166,4 +166,4 @@ test2008 test2009 test2010 test2011 test2012 test2013 test2014 test2015 \
 test2016 test2017 test2018 test2019 test2020 test2021 test2022 test2023 \
 test2024 test2025 test2026 test2027 test2028 test2029 test2030 test2031 \
 test2032 test2033 test2034 test2035 test2036 test2037 test2038 test2039 \
-test2040 test2041 test2042
+test2040 test2041 test2042 test2043

tests/data/test2043

@@ -0,0 +1,33 @@
+<testcase>
+<info>
+<keywords>
+HTTPS
+HTTP GET
+</keywords>
+</info>
+
+#
+# Client-side
+<client>
+<features>
+WinSSL
+</features>
+<server>
+none
+</server>
+ <name>
+Disable certificate revocation checks
+ </name>
+ <command>
+--ssl-no-revoke -I https://revoked.grc.com/
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<errorcode>
+0
+</errorcode>
+</verify>
+</testcase>