Initial implementation

This is an initial implementation of ShareDB's [`MilestoneDB`][1]. The
base bones of `MongoMilestoneDB` are based on the [`sharedb-mongo`][2]
database adapter.

This adapter is a slight departure from other ShareDB code, as it is
written in ES7 for easier maintenance, especially when dealing with
asynchronous code, as this gives us access to the `async`/`await`
notation (although we can't realise its full potential due to needing
to deal with consumer callbacks to be consistent with the rest of
ShareDB).

The move to ES7 drops support for Node v6.

This library notably uses v2 of [`mongodb`][3] instead of the newer v3.
This is to stay consistent with `sharedb-mongo`, so in theory the same
config (or style of config) can be used in both `sharedb-mongo` and in
`sharedb-milestone-mongo`.

The version of [`istanbul`][4] is also bumped to the alpha version to
[support ES7 syntax][5]. We also move away from `jshint` and use
`eslint` with some more aggressive linting.

[1]: share/sharedb#236
[2]: https://github.com/share/sharedb-mongo
[3]: https://mongodb.github.io/node-mongodb-native/
[4]: https://github.com/gotwarlost/istanbul
[5]: gotwarlost/istanbul#733

.eslintrc

@@ -0,0 +1,15 @@
+{
+  "extends": "./eslint.base.yaml",
+  "parserOptions": {
+    "ecmaVersion": 2017,
+    "sourceType": "module",
+    "ecmaFeatures": {
+      "modules": true
+    }
+  },
+  "env": {
+    "mocha": true,
+    "es6": true,
+    "node": true
+  }
+}

.gitignore

@@ -5,6 +5,9 @@ npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
 
+# IDEs
+.vscode
+
 # Runtime data
 pids
 *.pid

.travis.yml

@@ -0,0 +1,26 @@
+language: node_js
+
+node_js:
+  - "8"
+  - "10"
+
+services:
+  - docker
+
+env:
+  - MONGODB_VERSION="2.6"
+  - MONGODB_VERSION="3.6"
+  - MONGODB_VERSION="4.0"
+
+before_install:
+  - docker run -d -p 127.0.0.1:27017:27017 mongo:$MONGODB_VERSION
+
+before_script:
+  - until nc -z localhost 27017; do echo Waiting for MongoDB; sleep 1; done
+
+script:
+  - npm run test-cover
+
+# Send coverage data to Coveralls
+after_script:
+  - cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js

LICENSE

@@ -0,0 +1,21 @@
+Licensed under the standard MIT license:
+
+Copyright 2018 Alec Gibson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.