add support for next function: DAYS, ISFORMULA, RRI, DMIN, DMAX, DAVERAGE, DSTDEV, DSTDEVP, DCOUNT, DCOUNTA, DGET, DPRODUCT, VAR, VARP, DSUM, BITAND, BITOR, BITXOR, BITLSHIFT, BITRSHIFT, MAXIFS, MINIFS, TEXTJOIN, BESSELJ, BESSELK, BESSELY, BESSELI, NETWORKSDAYS.INTL, WORKDAY.INTL, SWITCH, ISOWEEKNUM, AGGREGATE, BINOM.DIST.RANGE, ECMA.CEILING, SHEET, SHEETS, UNICODE

Fix Bug 35408.

Update grunt to latest stable version

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

Feature/fix translation