As an API user I want to know how many databases carry matches to my name-string

[dimus]

One of quality assesments we use is number of databases where we found a match for a name-string.
It should be found for every name-string, and located on the same level as 'total', 'suppliedInput', 'suppliedId', for example:

matchedDataSources: 36

in this example matchedDataSources will always be 36 when we search full database (independant on bestMatchOnly true or false). It returns number of data_sources we found a name in.

In case where user specifically asked for dataSourceIds [1,2] it returns only number that was found in the subset of datasources. In the example it wold not exceed 2.

[alexander-myltsev]

closed by 0bd9b1a and 1a2fc0e