Upgrade ejs to fix security vulnerabilities

[djabif]

ejs 1.0.0 has known security vulnerabilities and should be updated to at least 2.5.5

What type of pull request are you creating?

• [ X] Bug Fix
• [ ] Enhancement
• [ ] Documentation

How many unit test did you write for this pull request?

none

Write a reason if none (e.g just fixed a typo):

Please add a description for your pull request:

ejs 1.0.0 has known security vulnerabilities and should be updated to at least 2.5.5 See:

• https://nvd.nist.gov/vuln/detail/CVE-2017-1000228
• https://nvd.nist.gov/vuln/detail/CVE-2017-1000188
• https://nvd.nist.gov/vuln/detail/CVE-2017-1000189

[jonathan-casarrubias]

@djabif I sent an answer for this in Twitter, but I'll answer in here as well,

In order to accept this patch we need to make sure that the ejs filters used in the builder are migrated.

https://github.com/mean-expert-official/loopback-sdk-builder/blob/master/lib/angular2/index.js#L20

Since those filters are deprecated in newer versions of EJS.

If you are able to fix that, I'll be glad to accept this patch

Cheers Jon