fix: remove keys from package.json after project is created

[rosen-vladimirov]

Remove confusing keys from project's package.json when Template v2 is used. Remove name and version as the users may decide we will use the values to set project name and version of the application.

PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/CONTRIBUTING.md#commit-messages.
• There is an issue for the bug/feature this PR is for. To avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it.
• You have signed the CLA.
• All existing tests are passing: https://github.com/NativeScript/nativescript-cli/blob/master/CONTRIBUTING.md#contribute-to-the-code-base
• Tests for the changes are included.

What is the current behavior?

After project is created and template v2 is used, the package.json contains a lot of confusing and unneeded keys:

{
  "nativescript": {
    "id": "org.nativescript.app7",
    "tns-android": {
      "version": "4.1.3"
    },
    "tns-ios": {
      "version": "4.1.1"
    }
  },
  "name": "tns-template-master-detail-ng",
  "displayName": "Master-Detail with Firebase",
  "templateType": "App template",
  "version": "4.1.2",
  "description": "NativeScript Application",
  "author": "Telerik <support@telerik.com>",
  "license": "SEE LICENSE IN <your-license-filename>",
  "keywords": [
    "telerik",
    "mobile",
    "nativescript",
    "{N}",
    "tns",
    "appbuilder",
    "template",
    "master-details",
    "detail",
    "category-general"
  ],
  "repository": "<fill-your-repository-here>",
  "homepage": "https://github.com/NativeScript/template-master-detail-ng",
  "bugs": {
    "url": "https://github.com/NativeScript/NativeScript/issues"
  },
  "scripts": {
    "lint": "tslint \"app/**/*.ts\""
  },
  "dependencies": {
    "@angular/animations": "~6.0.6",
    "@angular/common": "~6.0.6",
    "@angular/compiler": "~6.0.6",
    "@angular/core": "~6.0.6",
    "@angular/forms": "~6.0.6",
    "@angular/http": "~6.0.6",
    "@angular/platform-browser": "~6.0.6",
    "@angular/platform-browser-dynamic": "~6.0.6",
    "@angular/router": "~6.0.6",
    "nativescript-angular": "~6.0.6",
    "nativescript-imagepicker": "~6.0.0",
    "nativescript-plugin-firebase": "~6.0.0",
    "nativescript-theme-core": "~1.0.4",
    "nativescript-ui-listview": "~3.5.0",
    "tns-core-modules": "~4.1.0",
    "reflect-metadata": "~0.1.10",
    "rxjs": "~6.1.0",
    "zone.js": "~0.8.18"
  },
  "devDependencies": {
    "codelyzer": "~4.3.0",
    "nativescript-dev-sass": "~1.6.0",
    "nativescript-dev-typescript": "~0.7.0",
    "nativescript-dev-webpack": "~0.14.0",
    "tslint": "~5.10.0",
    "typescript": "~2.7.2",
    "@angular/compiler-cli": "~6.1.0-beta.3",
    "@ngtools/webpack": "6.1.0-rc.0"
  },
  "readme": "NativeScript Application"
}

What is the new behavior?

The package.json contains only required keys:

{
  "nativescript": {
    "id": "org.nativescript.app8",
    "tns-android": {
      "version": "4.1.3"
    },
    "tns-ios": {
      "version": "4.1.1"
    }
  },
  "description": "NativeScript Application",
  "license": "SEE LICENSE IN <your-license-filename>",
  "repository": "<fill-your-repository-here>",
  "scripts": {
    "lint": "tslint \"app/**/*.ts\""
  },
  "dependencies": {
    "@angular/animations": "~6.0.6",
    "@angular/common": "~6.0.6",
    "@angular/compiler": "~6.0.6",
    "@angular/core": "~6.0.6",
    "@angular/forms": "~6.0.6",
    "@angular/http": "~6.0.6",
    "@angular/platform-browser": "~6.0.6",
    "@angular/platform-browser-dynamic": "~6.0.6",
    "@angular/router": "~6.0.6",
    "nativescript-angular": "~6.0.6",
    "nativescript-imagepicker": "~6.0.0",
    "nativescript-plugin-firebase": "~6.0.0",
    "nativescript-theme-core": "~1.0.4",
    "nativescript-ui-listview": "~3.5.0",
    "tns-core-modules": "~4.1.0",
    "reflect-metadata": "~0.1.10",
    "rxjs": "~6.1.0",
    "zone.js": "~0.8.18"
  },
  "devDependencies": {
    "codelyzer": "~4.3.0",
    "nativescript-dev-sass": "~1.6.0",
    "nativescript-dev-typescript": "~0.7.0",
    "nativescript-dev-webpack": "~0.14.0",
    "tslint": "~5.10.0",
    "typescript": "~2.7.2",
    "@angular/compiler-cli": "~6.1.0-beta.3",
    "@ngtools/webpack": "6.1.0-rc.0"
  },
  "readme": "NativeScript Application"
}