release: prepare for 1.7.0

Written the changelog and updated package.json.

From now on, releases will be cut from develop, and merged directly into master.

Each release will be a tag on the master branch (e.g. 1.7.0).
A "release/1.7.0" branch will eventually be created only if/when a hotfix will
be needed.

CHANGELOG.md

+# 1.7.0
+* FIX: `getLineHTMLForExport()` no longer produces multiple copies of a line. **WARNING**: this could potentially break some plugins
+* FIX: authorship of bullet points no longer changes when a second author edits them
+* FIX: improved Firefox compatibility (non printable keys)
+* FIX: `getPadPlainText()` was not working
+* REQUIREMENTS: minimum required Node version is 6.9.0 LTS. The next release will require at least Node 8.9.0 LTS
+* SECURITY: updated MySQL, Elasticsearch and PostgreSQL drivers
+* SECURITY: started updating deprecated code and packages
+* DOCS: documented --credentials, --apikey, --sessionkey. Better detailed contributors guidelines. Added a section on securing the installation
+
 # 1.6.6
  * FIX: line numbers are aligned with text again (broken in 1.6.4)
  * FIX: text entered between connection loss and reconnection was not saved

src/package.json

@@ -79,6 +79,6 @@
   "scripts": {
     "test": "nyc mocha --timeout 5000 ../tests/backend/specs/api"
   },
-  "version": "1.6.6",
+  "version": "1.7.0",
   "license": "Apache-2.0"
 }