ci: determine last release from git tags

.travis.yml

@@ -13,6 +13,8 @@ cache:
     - $HOME/.composer/cache
 
 before_install:
+  - git config --replace-all remote.origin.fetch +refs/heads/*:refs/remotes/origin/*
+  - git fetch --tags
   - nvm install 8
   - nvm use 8
 

package.json

@@ -53,6 +53,7 @@
     "@types/semver": "^5.3.34",
     "cz-conventional-changelog": "^2.0.0",
     "husky": "^0.14.3",
+    "last-release-git": "0.0.3",
     "semantic-release": "^8.2.0",
     "tslint": "^5.0.0",
     "typescript": "^2.1.4",
@@ -70,6 +71,9 @@
       "path": "./node_modules/cz-conventional-changelog"
     }
   },
+  "release": {
+    "getLastRelease": "last-release-git"
+  },
   "contributes": {
     "configuration": {
       "type": "object",