Partially fixes #298 - make apps pluggable

[djmgit]

Partially fixes #298 - made apps pluggable

Partially fixes issue - #298, moved the following apps'
dependencies into their individual folders and updated
script and css references.

```
barchart
boilerplate
bubblecharts
collegeElections
compareTwitterProfiles
CountryTweetMap
ducphanduy
emojiheatmap
emojiheatmapper
fossasia-histogram
histogram
knowthediff
LQL
MultiLinePlotter

```

I have:

• There is a corresponding issue for this pull request.
• Mentioned the Issue number in the pull request commit message Fixes #<number> commit message
• There is only strictly only one commit per issue.

For the reviewers

I have:

• Reviewed this pull request by an authorized contributor.
• The reviewer is assigned to the pull request.

[vibhcool]

May be I will be wrong, but IMO images in the apps shall also be moved to images directory in the respective apps.

[kavithaenair]

@djmgit I think this PR will cause redundancy and space wastage.
As you can see the PR loklak/loklak_server#802, was to remove redundancy, but this PR may again cause the same issue.

[djmgit]

@kavithaenair Its true that this will introduce redundancy, presently the apps have got their dependencies distributed in different folders (like js and css in root directory), so the apps are not standalone. The aim of this PR is to make the apps standalone so that any one can use an app independently (simply copy the app folder and use it somewhere else without caring about the dependencies). But that is only possible when the apps have all their dependencies with them (In the same folder) or else users will also have to manage the app dependencies as well that is also take care of the root js, css and images folder which contains dependencies of all apps.
If we use some dependency management tool like bower then too we will have to maintain bower components in each directory which will again give rise to the same issue - redundancy.

@Achint08 @hemantjadon @vibhcool @kavithaenair @singhpratyush @SKrPl what do you all suggest?

[vibhcool]

IMHO Space shall not be much of the issue. If this PR keeps each app independent of each other and the website code and app code is kept separately, then this PR is fine.

[djmgit]

Test link: klakapps.surge.sh

@kavithaenair @vibhcool open for review.
I will be working on the remaining apps in subsequent PRs.