Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC revisions 260894,260899,262895-262902,262904,262908-262910,262982,
262984,263133-263137,263139,263141,263144-263150, and (partially) 263249
(31 revisions; summarized below)...
r260894: Optimize f_expand_number(), improving performance
r260899: s/__number/__num/ in f_expand_number()
r262895: Allow dispatched reswords to carry arguments
r262896: Add missing local declaration
r262897: Fix a typo in a comment
r262898: Fix incorrect return status if var_to_set and var_to_get are same
r262899: Make f_show_err non-fatal
r262900: Centralize function name; Update a comment while here
r262901: s/__num/__number/ in f_expand_number()
r262902: Comment to go with NL global introduced by previous commit
r262904: Rewrite groupmgmt -- hooking it into the scripting system
r262908: Change dispatch words from group* to *Group for backward compat
r262909: Fix copy/paste error in a comment
r262910: Take a group name on the command-line if available
r262982: Whitespace
r262984: Remove vestigial global, no longer used since r262904
r263133: Remove indexfile from debug statement (already logged)
r263134: Add debug statement just before attempting to exec a module
r263135: Comments
r263136: Update copyright
r263137: Fix future namespace issues for functions taking $var_to_set
r263139: Remove useless NULL string in compound strings
r263141: Pointy hat! Fix a broken f_isinteger()
r263144: Fix a code-typo that prevented auto-sizing of a dialog
r263145: Fix comments and whitespace
r263146: Reduce the sleep cycle when using dialog(1) [infobox] to 1-second
r263147: Fix a bug preventing errors from pw(8) from appearing
r263148: For non-interactive scripts, forgot to check argument
r263149: Add protection against input containing single-quotes
r263150: Rewrite usermgmt
r263249: (partial) Add more obsolete files

MFC r259054:
Performance and debugging enhancements:
+ Remove UNAME_P=$(...) from startup/misc -- already supplied by common.subr
+ Use f_getvar instead of $(eval echo \$$var) -- f_getvar is sub-shell free
+ Add `-e' and `-k var' options to f_eval_catch -- increasing use-cases
+ Use f_eval_catch to display errors on failure -- reducing duplicated code
+ Use f_eval_catch when we need output from a command -- improving debugging
+ Optimize f_isinter of strings.subr for performance -- now sub-shell free
+ Improve error checking on pidfiles -- using f_eval_catch and f_isinteger
+ Use $var_to_set arg of f_ifconfig_{inet,netmask} -- eliminate sub-shells
+ Use f_sprintf instead of $(printf ...) -- consolidate sub-shells
+ Use $var_to_set arg of f_route_get_default -- eliminate sub-shells
+ Add f_count to replace $(set -- ...;echo $#) -- eliminate sub-shells
+ Add f_count_ifs to replace $(IFS=x;set -- ...;echo $#) -- no sub-shells
+ Replace var="$var${var:+ }..." in loops with var="$var ..." with a follow-
up var="${var# }" to trim leading whitespace -- optimize loops
+ Use $var_to_set arg of f_resolv_conf_nameservers -- eliminate sub-shells
+ Comments for the f_eval_catch function
+ Remove a duplicate `local ... desc ...' in f_device_get_all of device.subr
+ Use $var_to_set arg of f_device_capacity -- eliminate sub-shells
+ Whitespace fixes in f_dialog_init of dialog.subr
+ Optimize f_inet_atoi of media/tcpip.subr for performance -- sub-shell free
+ In several cases, send stderr to /dev/null -- clean up runtime execution
+ Change f_err of common.subr to go to program stderr not terminal stderr,
allowing redirection of output from functions that use f_err
+ Disable debugging when using f_getvar to get variable argument to
f_startup_rcconf_map_expand of startup/rcconf.subr
+ Use f_replace_all instead of $(echo ... | tr | sed) -- performance
+ Add a $var_to_set option to f_index_{file,menusel_{command,keyword}} of
common.subr -- centralize sub-shells

MFC revisions 256321-256323,256331,256333,256335,256343:
Bring in a new zfsboot auto script for performing automatic setup of a boot
pool (optionally encrypted) with many other options, validations, features.
Originally submitted by Allan Jude; modified in collaboration.

MFC revisions 256325,256330,256345:
Rewrite the keymap selection menu to display keymaps and provide a test
mechanism. Test mechanism originally submitted by Warren Block; modified.

MFC r256347:
Prominently display "Wireless" for each wireless network interface. Part
of PR bin/161547; submitted by Warren Block; slightly modified.

MFC r256348:
Remove the dumpdev configuration dialog, merge it into the regular
services configuration and enable it by default. Originally submitted by
Allan Jude; slightly modified.

PR: bin/161547
Submitted by: Allan Jude, Warren Block <wblock@wonkity.com>
In collaboration with: Allan Jude <freebsd@allanjude.com>
Approved by: re (glebius)

Add keymap.subr for presenting custom keymap dialogs (with X11 support).

Approved by: re (glebius)