Upgrade base-x from 3.0.4 to 3.0.7 (#31)

On installing `ripple-lib`, a warning is thrown for @types/base-x@3.0.6
since base-x now has types included. By upgrading base-x to at least
3.0.6, we no longer need the stub types.

If we don't want to upgrade this dependency, an alternative approach
would be to version lock `@types/base-x` to 3.0.4.

packages/ripple-address-codec/package.json

@@ -10,8 +10,7 @@
   "types": "dist/index.d.ts",
   "license": "ISC",
   "dependencies": {
-    "@types/base-x": "^3.0.0",
-    "base-x": "3.0.4",
+    "base-x": "3.0.7",
     "create-hash": "^1.1.2"
   },
   "repository": {

packages/ripple-address-codec/yarn.lock

@@ -319,13 +319,6 @@
   dependencies:
     "@babel/types" "^7.3.0"
 
-"@types/base-x@^3.0.0":
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/@types/base-x/-/base-x-3.0.0.tgz#a1365259d1d3fa3ff973ab543192a6bdd4cb2f90"
-  integrity sha512-vnqSlpsv9uFX5/z8GyKWAfWHhLGJDBkrgRRsnxlsX23DHOlNyqP/eHQiv4TwnYcZULzQIxaWA/xRWU9Dyy4qzw==
-  dependencies:
-    "@types/node" "*"
-
 "@types/istanbul-lib-coverage@*", "@types/istanbul-lib-coverage@^2.0.0":
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/@types/istanbul-lib-coverage/-/istanbul-lib-coverage-2.0.1.tgz#42995b446db9a48a11a07ec083499a860e9138ff"
@@ -358,11 +351,6 @@
   dependencies:
     "@types/jest-diff" "*"
 
-"@types/node@*":
-  version "12.7.7"
-  resolved "https://registry.yarnpkg.com/@types/node/-/node-12.7.7.tgz#f9bd8c00fa9e1a8129af910fc829f6139c397d6c"
-  integrity sha512-4jUncNe2tj1nmrO/34PsRpZqYVnRV1svbU78cKhuQKkMntKB/AmdLyGgswcZKjFHEHGpiY8pVD8CuVI55nP54w==
-
 "@types/node@^10.12.0":
   version "10.14.19"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-10.14.19.tgz#f52742c7834a815dedf66edfc8a51547e2a67342"
@@ -598,10 +586,10 @@ balanced-match@^1.0.0:
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
   integrity sha1-ibTRmasr7kneFk6gK4nORi1xt2c=
 
-base-x@3.0.4:
-  version "3.0.4"
-  resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.4.tgz#94c1788736da065edb1d68808869e357c977fa77"
-  integrity sha512-UYOadoSIkEI/VrRGSG6qp93rp2WdokiAiNYDfGW5qURAY8GiAQkvMbwNNSDYiVJopqv4gCna7xqf4rrNGp+5AA==
+base-x@3.0.7:
+  version "3.0.7"
+  resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.7.tgz#1c5a7fafe8f66b4114063e8da102799d4e7c408f"
+  integrity sha512-zAKJGuQPihXW22fkrfOclUUZXM2g92z5GzlSMHxhO6r6Qj+Nm0ccaGNBzDZojzwOMkpjAv4J0fOv1U4go+a4iw==
   dependencies:
     safe-buffer "^5.0.1"