Continue testing unsupported versions

They are no longer supported by their vendors, but until we do support
them, we should continue testing them.

.travis.yml

@@ -104,6 +104,9 @@ jobs:
  - stage: Test
  php: 7.3
  env: DB=mysqli.docker IMAGE=mysql:8.0 COVERAGE=yes
+ - stage: Test
+ php: 7.3
+ env: DB=mariadb.docker IMAGE=mariadb:10.0 COVERAGE=yes
  - stage: Test
  php: 7.3
  env: DB=mariadb.docker IMAGE=mariadb:10.1 COVERAGE=yes
@@ -113,6 +116,9 @@ jobs:
  - stage: Test
  php: 7.3
  env: DB=mariadb.docker IMAGE=mariadb:10.3 COVERAGE=yes
+ - stage: Test
+ php: 7.3
+ env: DB=mariadb.mysqli.docker IMAGE=mariadb:10.0 COVERAGE=yes
  - stage: Test
  php: 7.3
  env: DB=mariadb.mysqli.docker IMAGE=mariadb:10.1 COVERAGE=yes
@@ -122,6 +128,22 @@ jobs:
  - stage: Test
  php: 7.3
  env: DB=mariadb.mysqli.docker IMAGE=mariadb:10.3 COVERAGE=yes
+ - stage: Test
+ dist: trusty
+ php: 7.3
+ env: DB=pgsql POSTGRESQL_VERSION=9.2 COVERAGE=yes
+ services:
+ - postgresql
+ addons:
+ postgresql: "9.2"
+ - stage: Test
+ dist: trusty
+ php: 7.3
+ env: DB=pgsql POSTGRESQL_VERSION=9.3 COVERAGE=yes
+ services:
+ - postgresql
+ addons:
+ postgresql: "9.3"
  - stage: Test
  php: 7.3
  env: DB=pgsql POSTGRESQL_VERSION=9.4 COVERAGE=yes