[EMF Compare CLI] Documentation of the 'logicalcherry-pick command'

Change-Id: Ib7eb8efbba63892fc372cc058febf73f6c0d3436
[EMF Compage CLI] Adds a "Known issues" section.

Adds a new "Known issues".
Adds reference to bug 451159.

Change-Id: Ie198e0ec75becc0aeb191ba0cc6e7cceb99e1c2f