Update to 2.9.2

Upstream changes:
2018 January 2

GNU nano 2.9.2 "Pussy Riot" correctly displays the Modified
state when undoing/redoing (also when the file was saved
somewhere midway), improves the undoing of an automatic
linefeed at EOF, fixes a build issue on the BSDs, shows
the cursor again when compiled with --withslang, renames
the option 'justifytrim' to 'trimblanks' because it will
now snip trailing whitespace also while you are typing
(and hard-wrapping is enabled), continues pushing words
to the next line much longer (when hard-wrapping), makes
 and  indent and unindent a marked region,
allows unindenting when not all lines are indented, lets a
region marked with Shift persist when indenting/unindenting
or commenting/uncommenting it, and in those cases excludes
the last line of the region when it is not visibly marked
(which makes for a more intuitive behavior).


(wen)