euci: implement get_t and set_t method

These are intended to be used as smart wrappers on top of get_* and
set_* methods. In case of get_t method you can specify type you are
expecting like a python type (str, bool and int). In case of set_t is
type autodetected from provided value.
1 job for get_t in 17 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
passed #268385
unittests

00:00:17