Implement endpoint for the config-server to search the configuration files' content

[MariusBrill]

We need a function to search for files based on their contents. This function would take a search string as an argument and returns the names of all files which contain this search string.

[AlexanderWert]

"... and retunrs the names of all files..."
--> Plus the corresponding line numbers in the files where the string has been found

[mariusoe]

The response of the endpoint should contain JSON object which describes the search hits.

A hit could be something like:

{
    line: 10,
    start: 40,
    end: 50
}

,where the line represents the line-number of the hit and start and end the position of the term withing the line. In this example, the search functionallity will not consider search queries which spans multiple lines, thus, only within one line.

The search term should be passed to the endpoint via a request parameter. The endpoint could be look like: .../search?q=search_term
In this exmaple, the parameter q stands for "query".