update docs re CI migration

.github/pull_request_template.md

@@ -1,4 +1,4 @@
 <!-- Note: Our primary focus is supporting Bitcoin, and contributions in that regard are appreciated the most!
 Due to historical reasons, ElectrumX also has support for many altcoins. These will be kept as long as
 maintenance burden can be kept *at a minimum*. When adding a new altcoin, (1) add a unit test (see tests/blocks),
-and (2) make sure the Travis tests pass. -->
+and (2) make sure the CI tests pass. -->

README.rst

@@ -1,5 +1,5 @@
-.. image:: https://travis-ci.org/spesmilo/electrumx.svg?branch=master
-    :target: https://travis-ci.org/spesmilo/electrumx
+.. image:: https://api.cirrus-ci.com/github/spesmilo/electrumx.svg?branch=master
+    :target: https://cirrus-ci.com/github/spesmilo/electrumx
 .. image:: https://coveralls.io/repos/github/spesmilo/electrumx/badge.svg
     :target: https://coveralls.io/github/spesmilo/electrumx
 

docs/index.rst

@@ -2,8 +2,8 @@
 ElectrumX
 =========
 
-.. image:: https://travis-ci.org/spesmilo/electrumx.svg?branch=master
-    :target: https://travis-ci.org/spesmilo/electrumx
+.. image:: https://api.cirrus-ci.com/github/spesmilo/electrumx.svg?branch=master
+    :target: https://cirrus-ci.com/github/spesmilo/electrumx
 .. image:: https://coveralls.io/repos/github/spesmilo/electrumx/badge.svg
     :target: https://coveralls.io/github/spesmilo/electrumx
 
@@ -22,8 +22,8 @@ Source Code
 ===========
 
 The project is hosted on `GitHub
-<https://github.com/spesmilo/electrumx/>`_.  and uses `Travis
-<https://travis-ci.org/spesmilo/electrumx>`_ for Continuous
+<https://github.com/spesmilo/electrumx/>`_.  and uses `Cirrus CI
+<https://cirrus-ci.com/github/spesmilo/electrumx>`_ for Continuous
 Integration.
 
 Please submit an issue on the `bug tracker