update Travis to R 4.0.0 and bionic

.travis.yml

@@ -2,7 +2,14 @@
 
 language: c
 sudo: required
-dist: trusty
+dist: bionic
+
+jobs:
+  include:
+    #- name: r-3.5
+    #  env: R_VERSION="3.5"
+    - name: r-4.0
+      env: R_VERSION="4.0"
 
 before_install:
   - curl -OLs https://eddelbuettel.github.io/r-travis/run.sh && chmod 0755 run.sh

ChangeLog

@@ -2,6 +2,8 @@
 
 	* DESCRIPTION (Version, Date): Release 0.0.6
 
+	* .travis.yml: Switch to bionic and R 4.0.0
+
 2020-06-08  Joseph Stachelek  <stachel2@msu.edu>
 
 	* R/binb.R: Update natbib default from 'none' to 'default' to please

inst/NEWS.Rd

@@ -10,6 +10,7 @@
     \item The README.md file received another badge (Dirk).
     \item The \code{natbib} default value was updated to accomodate
     \pkg{rmarkdown} (Joseph Stachelek in \ghpr{26}).
+    \item Travis now uses R 4.0.0 and 'bionic' (Dirk).
   }
 }