chore(deps): support Angular 5, remove @angular/http references

[AHelper]

Support Angular 4 & 5 dependencies, remove references to deprecated @angular/http module in favor of @angular/common/http

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines: https://github.com/HackedByChinese/ng2-idle/blob/master/CONTRIBUTING.md#pr
• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x")

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior? (You can also link to an open issue here)

See #68 and #69.

What is the new behavior?

Does this PR introduce a breaking change? (check one with "x")

[x] Yes
[ ] No

• Support for Angular 2.x dropped due to missing @angular/common/http dependency

Other information:

Also, are tests in master currently broken, or is my environment acting up? Getting 30 failed test cases...

[moribvndvs]

Thanks for the PR! I think it's related to changes in how zones are used. I haven't run into issues running tests on 2 and 4. I'll see if I can dig into how to properly work with intervals and zones (ugh).