Many library improvements.

Many library improvements.

Major changes:
+ Introduced SSHKywords.Run_Keyword_Preserve_Connection.
+ Most ClusterManagement keywords should not affect active SSH connection anymore.

Minor improvements:
+ CarPeople.Set_Variables_For_Shard also sets \${${shard_name}_first_follower_index}.
+ ClusterManagement variables sorted.
+ ${KARAF_HOME} constructed in ClusterManagement.
+ ClustwerManagement.Get_Owner_And_Candidates_For_Type_And_Id added.
+ Start_Members_From_List_Or_All checks sync only once per 10 seconds.
+ Renamed Run_Command_On_* to Run_Bash_Command_On_*.
+ Introduced Run_Karaf_Command_On_*.
+ Clean_Directories_* and Install_Feature_* addd to ClusterManagement.
+ (Unsafe) With_Ssh_To_List_Or_All_Run_Keyword and Safe_* added.
+ Restore_Current_Ssh_Connection_From_Index moved from KarafKeywords to SSHKeywords.
+ Introduced KarafKeywords.Safe_Issue_Command_On_Karaf_Console.
+ SSHKeywords.Open_Connection_To_* take ${ip_address} as an optional argument.
+ Karaf EOF workaround added to SetiupUtils.Setup_Utils_For_Setup_And_Teardown.

Change-Id: Ia61abe2bdaa15f90e3042742275ddbd45b4fc72d
Signed-off-by: Vratko Polak <vrpolak@cisco.com>