Specify format of UserAgent-Header

[ubamrein]

With the new release, the android sdk changed the header by appending the version of the used EN-Framework. Currently, we are checking for exactly 5 parts as can be seen here:

dp3t-sdk-backend/dpppt-backend-sdk/dpppt-backend-sdk-ws/src/main/java/org/dpppt/backend/sdk/ws/insertmanager/InsertManager.java

Line 107 in 288d099

if (headerParts.length != 5) {

For now, we should change the condition to >=5, to account for the added properties.

I think ultimately we should sit together with the app-sdk people and define a specific format (e.g. a map) to make the parsing more robust to changes and additions.