RPM 4.19.x bugfix release

[pmatilai]

There are some pretty nasty bugs in 4.19.1 still, I think we should put out an expedited bugfix release to address at least these regressions:

• Make user/group lookup caching thread-safe #2843
• Fix regression in Lua scriptlet runaway child detection #2818

Other, less nasty stuff:

• Don't warn about missing user/group on skipped files #2814
• Print full path if file removal fails #2806

Plus a whole pile of various build-related fixes:

• Fix unconditional uses of Linux-specific extensions #2812
• Don't use _nl_msg_cat_cntr if it's not available #2856
• CMakeLists.txt: restore readline support as an explicit option #2852
• don't attempt to install html pages if they're not built #2848

That's just from the top of my head, there's almost certainly more. As these are all bugfixes only, it might make sense to call it 4.19.1.1 rather than 4.19.2 (but that's just numbers...)

[dmnks]

Ack, thanks for creating the ticket!

[dmnks]

• Print full path if file removal fails #2806

Just FTR, this one already is in 4.19.1.