doc/modules/index: Only list modules which have the 'doc' directory

refs #4820
Display a message when a list view is empty

fixes #6469
Display note when host and service is not found

When the show/host and show/service views do not find a host or service,
don't show a non-working view, but display a error message

fixes #6469
Fix violations of coding guidelines
Do not expect a particular exception message

refs #6542
Add files to skip during coverage generation to the global ignore list

refs #6091
Remove @codeCoverageIgnoreStart/-Stop annotations

refs #6091
Remove @codingStandardsIgnoreStart/-Stop annotations

refs #6091
Merge branch 'bugfix/get-rid-of-line-based-annotations-6091'

fixes #6091
Remove missed echo instruction for debug purposes
doc module: Move `DocException' beneath `Exception' namespace

There are more exceptions to come which also will be beneath the `Exception' namespace.

refs #4820
doc module: Add `ChapterNotFoundException'

refs #4820
doc module: Add `DocEmptyException'

refs #4820
doc module: Add `DocIterator::count()'

Method used to count available markdown documentation files.

refs #4820
doc module: Let `DocParser' throw `DocEmptyException' and `ChapterNotFound' exception

`DocEmptyException' is thrown during construction when a documentation directory is empty.
`ChapterNotFound' is thrown when a chapter was not found when calling `getChapter()'.

refs #4820
doc module: Respond with 404 if a chapter was not found or the doc directory is empty

refs #4820
js/loader: handle form redirections automagically

An XHR redirection in a right-side container pointing to the URL
shown on the left should close it's own container and refresh the
lefthand one.

refs #6436
fixes #6435
Fix violation of coding guidelines
Fix the DbBackendFormTest

Mock ResourceFactory in form tests

fixes #6596
Fix ResourceFormTest

Add function-mock for mysqlAvaialable to prevent the unit test from breaking