Merge topic 'ep-url-special-characters'

54cb65b197 ExternalProject: Prevent URL list-splitting on special characters
aab6be9aad ExternalProject: Catch empty REMOTE or LOCAL earlier
e72791ecf6 ExternalProject: Update foreach() calls to use IN LISTS and IN ITEMS
873b2ad2eb ExternalProject: Remove N^2 add_dependencies() calls

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !9193