Update manual.tex

Trying to install Cuckoo in Juno with ADT version 23.0.2, throw following error:
"No repository found containing: osgi.bundle,com.android.ide.eclipse.adt,23.0.3.1327240"

Unchecking "Contact all update sites during install to find required software" solved the problem. manual.pdf in the same directory should also be updated with this change.