[tests] set timeout for OS_GetHost() tests to 10 seconds; thanks to @awiddersheim
better file handling on update:

always overwrite internal_options.conf
only write local_internal_options.conf if it not exists
only write client.keys if it not exists
Merge pull request #363 from cgzones/unit_test_timeout

[tests] set timeout for OS_GetHost() tests to 10 seconds
Merge pull request #364 from cgzones/install_config

better file handling on update