Make abbreviations expand on quotes as well as space.

Also added rough documentation for insert mode.

TODO: Abbreviations should also expand on <CR> and <Tab>, but right now
adding <CR> to the mappings.add() has no effect, and adding <Tab> to the
mappings.add() breaks tab completion.

TODO: Rather than listing non-keyword characters in two places (ui.js
and mappings.js), they should be specified in one location (that could
someday be trumped by an 'iskeyword' option).

vimperator/locale/en-US/insert.txt

@@ -0,0 +1,30 @@
+HEADER
+
+|Insert-mode| |Insert| |mode-insert| +
+
+Insert mode is used to enter text in text boxes and text areas. When
+'insertmode' is set, focusing on a text area immediately switches to
+insert mode.
+
+|i| +
+||i||
+________________________________________________________________________________
+Starts insert mode in text areas when 'insertmode' is not set.
+________________________________________________________________________________
+
+
+section:Insert-mode{nbsp}special{nbsp}keys[ins-special-keys]
+
+|i_<C-i>| +
+||<C-i>||
+________________________________________________________________________________
+Launch the external editor. See the 'editor' option.
+________________________________________________________________________________
+
+|i_<C-]>| +
+||<C-]>||
+________________________________________________________________________________
+Expand an insert-mode abbreviation.
+________________________________________________________________________________
+
+// vim: set filetype=asciidoc: