wait_for_comm_cycle to wait for uptime
wait_for_comm_cycle to wait for uptime

- Modify wait_for_comm_cycle() to wait for uptime to be less than
  elapsed_boot_time.  It will no longer insist that packet_loss reach
  100 and that it then reach 0.
- Modify compare_states() function to evaluate python expressions in
  addition to processing regular expressions.
- Modify get_state to get elapsed_boot_time
- Miscellaneous cleanup:
  - valid_value, etc. no longer needs to be fed var_name.
  - "Description of arguments" syntax was not adhering to standard.
- Changed anchor_state() and strip_anchor_state() to stop reading
  values from state dictionary.  The first goal was to stop using
  the name match_state_value since the function need not presume that
  the dictionary is a match dictionary.

Change-Id: I7d958c7a98ca879949414a20ecbc7cb86204709a
Signed-off-by: Michael Walsh <10404802c7de463f402c4a18638106ca1b12ef61@us.ibm.com>

openbmc/openbmc-test-automation,openbmc/openbmc-test-automation