BLD: add py38 and bump osx to 10.9

Author: tacaswell

.travis.yml

@@ -43,25 +43,40 @@ matrix:
         - MB_PYTHON_VERSION=3.7
         - NP_BUILD_DEP="1.14.5"
         - NP_TEST_DEP="1.14.5"
+    - os: linux
+      env:
+        - MB_PYTHON_VERSION=3.8
+        - NP_BUILD_DEP="1.14.5"
+        - NP_TEST_DEP="1.14.5"
+
     - os: linux
       env:
         - MB_PYTHON_VERSION=3.7
         - PLAT=i686
         - NP_BUILD_DEP="1.14.5"
         - NP_TEST_DEP="1.14.5"
+
     - os: osx
       language: generic
       env:
         - MB_PYTHON_VERSION=3.6
+        - MB_PYTHON_OSX_VER=10.9
         - NP_BUILD_DEP="1.11.3"
         - NP_TEST_DEP="1.11.3"
     - os: osx
       language: generic
       env:
         - MB_PYTHON_VERSION=3.7
+        - MB_PYTHON_OSX_VER=10.9
         - NP_BUILD_DEP="1.14.5"
         - NP_TEST_DEP="1.14.5"
-
+    - os: osx
+      language: generic
+      env:
+        - MB_PYTHON_VERSION=3.8
+        - MB_PYTHON_OSX_VER=10.9
+        - NP_BUILD_DEP=1.14.5
+        - NP_TEST_DEP=1.14.5
 before_install:
     # See:
     # https://github.com/travis-ci/travis-ci/issues/8920#issuecomment-352661024