Added test cases for clock management

What all is added:
    - Added test case to set BMC and HOST Time
        for all good path scenarios
    - Added test case to set BMC and HOST Time
        for all bad path scenarios
    - These TCs are also added in skip list due
        to an existing issue
    - Added keyword to get BMC and HOST time. This
        keyword is used to verify set time operation.
    - Updated minimum cell separator of 2 spaces
    - Updated documentation section
    - All lines are now under 79 characters

Resolves openbmc/openbmc-test-automation#227 and
         openbmc/openbmc-test-automation#271

Change-Id: I15a4915caf1a212272c390f12b949e76748c1664
Signed-off-by: Rahul Maheshwari <rahulmaheshwari@in.ibm.com>
5 files changed