core: set_put never returns -EEXIST When the value is already there it returns 0. Also add a test to ensure this
remove unused includes This patch removes includes that are not used. The removals were found with include-what-you-use which checks if any of the symbols from a header is in use.
test: only use assert_se The asserts used in the tests should never be allowed to be optimized away
tests: add tests for {hashmap,set}_steal_first Just to make sure that coverity is wrong.