[WIP] GSoC Idea - Add 500 error page

[Shekharrajak]

Fixes # GSoC Idea - Add 500 error page

Changes proposed in this pull request:

• if there is any HTTP request is sent from the Angular application and response it 500 status code, it will redirect to 500 page (InternalServerComponent)

• Link to live demo: http://pr-XXX-evalai.surge.sh

TODOs / Future work :

• [ ] For error-page a separate module can be created and imported to app module for lazy loading.
• [ ] error-page uses a service that redirect to 500 page , similar things can be done for 404, 400 or other status code.
• [ ] move the not-found component in error-page folder.
• [ ] services related to errors and error handler can be rearranged in one folder.
• [ ] Write testcase for the changes

[sanketbansal]

I have created a PR #122 for the proposed changes. please have a look.

[RishabhJain2018]

@Shekharrajak Is this PR complete or still WIP?

[Shekharrajak]

@RishabhJain2018 , I think, @sanketbansal should cherry-pick commits from this branch and merge(rebase) it with #122 . Then @sanketbansal can do his changes(may be his the UI page work for 500) and add testcases for it.

[RishabhJain2018]

Cool. @sanketbansal Can you please make sure that you don't forget this.

[sanketbansal]

yeah, I have checked this PR but it has no as such commits to be cherrypicked for #122 as many changes have already been committed in #122 which are quite similar to this PR.

[sanketbansal]

Although, if it is required then I can do that.

[Shekharrajak]

It looked like you saw the Rishabh's comment today. I replied here, please have a look.