Mention update to machinefile in `NEWS`.
Merge pull request #8888 from wavexx/machinecount_news

Mention update to machinefile in `NEWS`.
Define eltype for Factorizations
Modal prefix history search.

Attempt to deal with down arrow better at end of history.
Refine prefix matching condition to consider mode changes as different.
Exit prefix searching mode on ctrl+C.
No need to reset history provider when resetting PrefixHistoryPrompt.
Pass thru keypresses to parent mode.
Cleanup some mess with types in LineEdit.jl
Fix lineedit test failure.