Merge topic 'find_item-consistent-behavior-cache-variables'

08db1341a6 find_*: ensure consistent behavior for cache variables
f5fa6d53b0 class cmake: Store working directory at cmake launch
b1729200c3 find_*: refactor cache variable handling

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !6110