Merge f4aa7f0 into 0b5e8d6

.travis.yml

@@ -3,9 +3,9 @@ language: ruby
 cache: bundler
 bundler_args: --deployment
 rvm:
-  - 2.4.6
-  - 2.5.5
-  - 2.6.3
+  - 2.4.7
+  - 2.5.6
+  - 2.6.4
   - 2.7.0-preview1
 before_install:
   # https://github.com/travis-ci/travis-ci/issues/8978#issuecomment-354036443

Gemfile.lock

@@ -6,8 +6,8 @@ GEM
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    addressable (2.6.0)
-      public_suffix (>= 2.0.2, < 4.0)
+    addressable (2.7.0)
+      public_suffix (>= 2.0.2, < 5.0)
     ast (2.4.0)
     buftok (0.2.0)
     charlock_holmes (0.7.6)
@@ -62,12 +62,12 @@ GEM
     memoizable (0.4.2)
       thread_safe (~> 0.3, >= 0.3.1)
     method_source (0.9.2)
-    mime-types (3.2.2)
+    mime-types (3.3)
       mime-types-data (~> 3.2015)
-    mime-types-data (3.2019.0331)
+    mime-types-data (3.2019.0904)
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
-    minitest (5.11.3)
+    minitest (5.12.0)
     multipart-post (2.1.1)
     naught (1.1.0)
     netrc (0.11.0)
@@ -76,12 +76,12 @@ GEM
     opus-ruby (1.0.1)
       ffi
     parallel (1.17.0)
-    parser (2.6.3.0)
+    parser (2.6.4.1)
       ast (~> 2.4.0)
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
-    public_suffix (3.1.1)
+    public_suffix (4.0.1)
     rainbow (3.0.0)
     rake (12.3.3)
     rbnacl (3.4.0)
@@ -142,7 +142,7 @@ GEM
       unf_ext
     unf_ext (0.0.7.6)
     unicode-display_width (1.6.0)
-    webmock (3.6.2)
+    webmock (3.7.5)
       addressable (>= 2.3.6)
       crack (>= 0.3.2)
       hashdiff (>= 0.4.0, < 2.0.0)

README.md

@@ -37,6 +37,7 @@ gem install bundler
 * zlib-devel
 * which
 * sqlite-devel
+* gdbm-devel
 
 ```bash
 cd /path/to/rgrb