bpo-33522: Enable CI builds on Visual Studio Team Services (#6865)

diff --git a/.vsts/linux-deps.yml b/.vsts/linux-deps.yml
new file mode 100644
index 0000000..b6c8a36
--- /dev/null
+++ b/.vsts/linux-deps.yml
@@ -0,0 +1,36 @@
+# Note: this file is not currently used, but when template support comes to VSTS it
+# will be referenced from the other scripts..
+
+# Current docs for the syntax of this file are at:
+#  https://github.com/Microsoft/vsts-agent/blob/master/docs/preview/yamlgettingstarted.md
+
+parameters:
+  OPENSSL: 1.1.0g
+  OPENSSL_DIR: "$(build.sourcesDirectory)/multissl/openssl/$(OPENSSL)"
+
+steps:
+- script: echo "deb-src http://archive.ubuntu.com/ubuntu/ xenial main" > /etc/apt/sources.list.d/python.list && sudo apt-get update
+  displayName: 'Update apt-get lists'
+
+- script: echo ##vso[task.prependpath]$(OPENSSL_DIR)
+  displayName: 'Add $(OPENSSL_DIR) to PATH'
+- script: >
+    sudo apt-get -yq install
+    build-essential
+    zlib1g-dev
+    libbz2-dev
+    liblzma-dev
+    libncurses5-dev
+    libreadline6-dev
+    libsqlite3-dev
+    libssl-dev
+    libgdbm-dev
+    tk-dev
+    lzma
+    lzma-dev
+    liblzma-dev
+    libffi-dev
+    uuid-dev
+  displayName: 'Install dependencies'
+- script: python3 Tools/ssl/multissltests.py --steps=library --base-directory $(build.sourcesDirectory)/multissl --openssl $(OPENSSL) --system Linux
+  displayName: 'python multissltests.py'