Migrate to ktor client and kotlinx.serialization (#100)

.idea/codeStyles/Project.xml

common/build.gradle.kts

...onMain/kotlin/com/studo/campusqr/common/ClientPayloads.kt

moderatorFrontend/build.gradle.kts

.../kotlin/views/accessManagement/AccessManagementDetails.kt

...anagement/accessManagementOverview/AccessManagementRow.kt

...end/src/main/kotlin/views/guestCheckIn/AddGuestCheckIn.kt

...iews/guestCheckIn/guestCheckInOverview/GuestCheckInRow.kt

...orFrontend/src/main/kotlin/views/locations/AddLocation.kt

...lin/views/locations/locationsOverview/LocationTableRow.kt

moderatorFrontend/src/main/kotlin/views/login/MailLogin.kt

moderatorFrontend/src/main/kotlin/views/report/Report.kt

moderatorFrontend/src/main/kotlin/views/users/AddUser.kt

...ratorFrontend/src/main/kotlin/views/users/UserTableRow.kt

moderatorFrontend/src/main/kotlin/webcore/NetworkManager.kt

...r/src/main/kotlin/com/studo/campusqr/database/Payloads.kt

...n/kotlin/com/studo/campusqr/endpoints/AccessManagement.kt

...rc/main/kotlin/com/studo/campusqr/endpoints/ReportData.kt