Release version 0.42.0.
Announce 0.42.0 release.
Update documentation for 0.42.0.
Add a little more description of exchange.vim plugin.
Use <code/> for samples and keys.

Having these properly marked with a tag allows the CSS to highlight them.
Before a mixture of single quotes, double quotes and <tt/> was used.

Fixes #408.
Add information about @: register.
Add CSS styling for <code> blocks.
Add some more <code> tags to documentation.
Add a couple more <code> tags and tweak <code> css.
Fix whitespace.

File was a mixture of tabs and spaces, revert to spaces.
Prevent cursor movement to save selection.

When switching from insert to temporary visual mode, the insert mode
leaving commands would move the caret. This would then result in erratic
behaviour, including resetting the selection upon a double-click.

Fixes #402.
Fix caret type when UI selection is used.

Since Vrapper isn't driving the selection, the caret type might need to
be switched depending on the direction and type of selection.

This doesn't apply for exclusive selection mode where the caret is a
simple vertical bar.
Update unstable update site.
Fix #410.  Don't delete pending characters in InsertMode mappings if
keypresses don't correspond to printable characters (alt or ctrl keys).
Update unstable update site.
Fix #412.  Add searches from '*' and '#' to history for command-line
searches.
Update unstable update site.
Add option scoping: local, global, default.

Global options are always set for all editors at the same time, even
when :setlocal is used.

Local options are always local, even when :set is used.

Default makes it depend on whenther :set or :setlocal was used.

Tests will use default value for local options.

Also make sure to call LocalConfigurationListeners when setlocal is
used.
Implement 'modifiable' for normal and visual mode.

TextContent implementations are wrapped with a decorator which monitors
the state of the 'modifiable' setting. If 'false', no replace or
inserts will be allowed, instead they will be silently ignored (similar
to what happens for Eclipse editors where isEditable() returns false).
Implement 'modifiable' for insert mode.

If modifiable is false, any keys other than navigation are suppressed,
making sure the user doesn't modify the buffer.