Fixing the bug with CallProcessError openssl.

It wasn't related to openssl.

src/zc/buildout/buildout.py

@@ -1208,6 +1208,17 @@ def _install_and_load(spec, group, entry, buildout):
                 dest = buildout_options['eggs-directory']
                 path = [buildout_options['develop-eggs-directory']]
 
+            # parse signature list
+            signature_certificate = buildout_options.get(
+              '__networkcache__signature-certificate-list')
+            if signature_certificate is not None:
+              cert_marker = '-----BEGIN CERTIFICATE-----'
+              signature_certificate_list = [cert_marker + '\n' + q.strip() \
+                for q in signature_certificate.split(cert_marker) \
+                  if q.strip()]
+            else:
+              signature_certificate_list = None
+
             zc.buildout.easy_install.install(
                 [spec], dest,
                 links=buildout._links,
@@ -1226,8 +1237,7 @@ def _install_and_load(spec, group, entry, buildout):
                 upload_dir_url=buildout_options.get('__networkcache__upload-dir-url'),
                 signature_private_key_file=buildout_options.get(
                     '__networkcache__signature-private-key-file'),
-                signature_certificate_list=buildout_options.get(
-                    '__networkcache__signature-certificate-list'),
+                signature_certificate_list=signature_certificate_list,
                 shacache_cert_file=buildout_options.get(
                     '__networkcache__shacache-cert-file'),
                 shacache_key_file=buildout_options.get(