fixes a bug which made tests in modes without saveReponses to write back some data when test with saveReponses was opened before.

Explanation: The testmode comes later with getTestData and is set correctly in the RUNNING stage, while in LOADING stage it war still the testmode of the test before! So if we opened a test in TRIAL mode after running a test in HOT mode, the loading stage will be write back to backend. As a workaround, we reset to DEMO here, so while in loading stage `saveResponses` is always false.

As all tests of one login are always in the same mode, maybe it would be better to retrieve the testmode from the login instead by getTestData.

load unit fix: request extended by alias to get the correct restore point #261; linting errors ignored!

use TestState.CONNECTION to store type of connection for command-channel and visualize in group-monitor

rename TERMINATING to TERMINATED wo have the one reported to backend/monitor to be TERMINATED and teh internale state (former TERMINATED) wich cames when locking was successful to FINISHED (not LOCKED because possible future confusion)

handleCommand transferred to testcontroller-component; forced navigation (erase unlock-codes) works; unlock-codes transformed to component instead of dialog (works except after reload)

reason was, that in l. 398, when the MAXTIMELEFT is only read when testMode.saveResponses. Accidentally the testmode was applied after that, so when asking that, the testmode was DEMO with testMode.saveResponses = fals

fixes https://github.com/iqb-berlin/testcenter-frontend/issues/177