Update unstable update site.
Work on #218: Implement context menu for command line widget.
Work on #218: Implement CTRL-Y to yank command line selection.

See gVim's `modeless-selection` and `c_CTRL-Y` help topics, text gets
yanked into the system clipboard. Note that Vimhelp doesn't really say
whether it yanks into the X11 selection, clipboard or both.
HalfPageUpDownMotion was replaced by PageScrollMotion.
Implemented global position marks (A-Z and 0-9).

If capital or digit mark name is used with `m{A-Z0-9}` the mark is
considered global in VIM. So that goto mark operation will switch the
current buffer if necessary. Current implementation uses Eclipse
bookmarks for this feature which make global marks visible, manageable
and persistent across restarts.

In addition to existing goto mark operations `\{a-zA-Z0-9}` was added to
switch to the editor associated with the mark without changing current
position. Thus allowing for editor bookmarks, not position bookmark.
**WARNING**: might conflict with user mappings of `\`.
Fixed local marks.
Merge pull request #234 from igrekster/global-marks

Implemented global position marks (A-Z and 0-9).
Suggested for #218 by igrekster: yank full command line if no selection.
Global Marks: ignore editors with no files associated.
More consistent block mode selection.
getTextBounds expects a *VIEW* offset and returns relative bounds.
Removed redundant textWidget.
Merge pull request #235 from igrekster/blockwise-visial-mode-tweaks

Blockwise visial mode tweaks
Update unstable update site.
Enter visual block mode with Ctrl-Q in addition to Ctrl-V.  Ctrl-Q is
the Vim alternative since many users already have Ctrl-V bound to paste
(:help ctrl-q).
Ported argtextobj.vim plugin

This plugin provides a text-object `a` (argument).
See http://www.vim.org/scripts/script.php?script_id=2699
Fix current position in visual mode.

Adjusts current position in visual mode to point to the last selected
character, not the next one.
This fixes issues like:

```
          cursror
          |
 text worda wordb
          ~
          ^selection
```

Before the fix if `iw` is pressed both words will be selected:
```
                cursror
                |
 text worda wordb
      ~~~~~~~~~~~
      ^selection
```
With this fix:
```
          cursror
          |
 text worda wordb
      ~~~~~
      ^selection
```
This also applies to other motions that depend on the current position.
Updated version to match unstable update site
Updated argtextobj core version to match unstable update site
Added support for single argument function calls/declarations.