Merge branch 'master' into 4904-arv-web

diff --combined doc/_config.yml
index e40421f506d1c32ec03d96db73ea23c5a212de05,ab1eb9efabda2f79e967369d19e9cfa7f2bacb85..4469af290ae7c8ab0e7845ac9b0ae992537ef341
--- 1/doc/_config.yml
--- 2/doc/_config.yml
+++ b/doc/_config.yml
@@@ -13,6 -13,14 +13,14 @@@ arvados_workbench_host: localhos
  exclude: ["Rakefile", "tmp", "vendor"]
  
  navbar:
+   start:
+     - Getting Started:
+       - start/index.html.textile.liquid
+     - Quickstart:
+       - start/getting_started/firstpipeline.html.textile.liquid
+     - Common Use Cases:
+       - start/getting_started/sharedata.html.textile.liquid
+ 
    userguide:
      - Getting Started:
        - user/index.html.textile.liquid
@@@ -40,8 -48,6 +48,8 @@@
        - user/tutorials/tutorial-submit-job.html.textile.liquid
        - user/topics/tutorial-parallel.html.textile.liquid
        - user/topics/arv-docker.html.textile.liquid
 +    - Develop a web service:
 +      - user/topics/arv-web.html.textile.liquid
      - Reference:
        - user/topics/run-command.html.textile.liquid
        - user/reference/job-pipeline-ref.html.textile.liquid
@@@ -60,7 -66,6 +68,7 @@@
        - sdk/python/sdk-python.html.textile.liquid
        - sdk/python/python.html.textile.liquid
        - sdk/python/crunch-utility-libraries.html.textile.liquid
 +      - sdk/python/events.html.textile.liquid
      - Perl:
        - sdk/perl/index.html.textile.liquid
      - Ruby:

diff --combined sdk/python/arvados/events.py
index 5ee1d42bceca582b9298421163958ffe819f7020,7e8cdc3282113ad7984c9e9d93cdb187a0c77b4f..a26c70a38bb700ca4608b3c1a30c0ed407ca4254
--- 1/sdk/python/arvados/events.py
--- 2/sdk/python/arvados/events.py
+++ b/sdk/python/arvados/events.py
@@@ -13,12 -13,15 +13,15 @@@ _logger = logging.getLogger('arvados.ev
  
  class EventClient(WebSocketClient):
      def __init__(self, url, filters, on_event):
-         ssl_options = None
-         if re.match(r'(?i)^(true|1|yes)$',
-                     config.get('ARVADOS_API_HOST_INSECURE', 'no')):
-             ssl_options={'cert_reqs': ssl.CERT_NONE}
+         # Prefer system's CA certificates (if available)
+         ssl_options = {}
+         certs_path = '/etc/ssl/certs/ca-certificates.crt'
+         if os.path.exists(certs_path):
+             ssl_options['ca_certs'] = certs_path
+         if config.flag_is_true('ARVADOS_API_HOST_INSECURE'):
+             ssl_options['cert_reqs'] = ssl.CERT_NONE
          else:
-             ssl_options={'cert_reqs': ssl.CERT_REQUIRED}
+             ssl_options['cert_reqs'] = ssl.CERT_REQUIRED
          super(EventClient, self).__init__(url, ssl_options=ssl_options)
          self.filters = filters
          self.on_event = on_event
@@@ -123,7 -126,6 +126,7 @@@ def subscribe(api, filters, on_event, p
      if poll_fallback:
          _logger.warn("Websockets not available, falling back to log table polling")
          p = PollClient(api, filters, on_event, poll_fallback)
 +        p.daemon = True
          p.start()
          return p
      else: