MFC revisions 260894,260899,262895-262902,262904,262908-262910,262982,

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

git-svn-id: svn://svn.freebsd.org/base/stable/10@263980 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f