According to Maxim Kadushkin mocha tests was added long time ago
and not maintained.
So may to remove all togher, but for now - just update to latest.

Without it there is a lot of deprecated warningns
Warnings like this:
```
npm WARN deprecated minimatch@0.2.14: Please update to minimatch 3.0.2
or higher to avoid a RegExp DoS issue
npm WARN deprecated minimatch@0.3.0: Please update to minimatch 3.0.2 or
higher to avoid a RegExp DoS issue
npm WARN deprecated graceful-fs@1.2.3: graceful-fs v3.0.0 and before
will fail on node releases >= v7.0. Please update to graceful-fs@^4.0.0
as soon as possible. Use 'npm ls graceful-fs' to find it in the tree.
npm WARN deprecated tough-cookie@2.2.2: ReDoS vulnerability parsing
Set-Cookie https://nodesecurity.io/advisories/130
npm WARN deprecated node-uuid@1.4.8: Use uuid module instead
npm WARN deprecated jade@0.26.3: Jade has been renamed to pug, please
install the latest version of pug instead of jade
npm WARN deprecated graceful-fs@2.0.3: graceful-fs v3.0.0 and before
will fail on node releases >= v7.0. Please update to graceful-fs@^4.0.0
as soon as possible. Use 'npm ls graceful-fs' to find it in the tree.
```

It add grunt task `html_minify`, which was not used anywhere.
This module require old Grunt `~0.4.1` and with this module
grunt cannot be upgraded to newer versions

v4.4.1

ru->en

add support for functions: PERCENTILE.EXC, PERCENTILE.INC, PERCENTRANK.INC, PERCENTRANK.EXC, CONFIDENCE.NORM, CONFIDENCE.T, BINOM.DIST, BINOM.INV