Disabled mode now applies to newly opened files

The disabled mode feature (Ctrl+Shift+F12) now applies to files which
are opened after the command is run.  Previously it only applied to the
set of files which were open when it was run.

closes #929
Inconsistent spacing in get, set declaration
Bring code up to coding conventions

Bring some older code up to current conventions
Removed a bit of redundant info in Settings

SettingValue can now provide it's kind without unnecessary calculation
Fixed RequireQualifiedAccess usage

Several unions lacked the attribute that is used, by convention, on all
discriminated unions in the code base
Cleaned up some names

Now that RequireQualifiedAccess is used there is no need to postfix the
names with Value and Kind
Tightened up the way default values are handled
Added the 'path' and 'cdpath' settings

This adds support for the 'path' and 'cdpath' options.  These options
are simply present at the moment.  No existing functionality takes
advantage of them at the moment. This is a necassary building block for
other features.
<Leader> replacement should be case insensitive

The <Leader> replacement was incorrectly doing case sensitive
replacement instead of case insensitive replacement.

closes #860
Removed UseEditorSettings

The UseEditorSettings option was an ancient option that I added when my
support of Vim settings and synchronization with the editor was
extremely poor.  It was a way to opt out of my bad behavior.

Now the settings support is much better.  Instead of this option we use
the presence or abscence of the VimRC file to determine if VsVim or
Visual Studio settings should win
Minor refactor of tests
Fixed delete inner quote bug

The quoted string code wasn't properly handling the case where the caret
was positioned on a quote character.  Changed it match the vim logic

closes #960
Fixed loading of window settings

Previous changes fixed the loading of local settings such thath the
vimrc file would always be preferred.  Unfortunately the window specific
settings were being handled different that local settings when it came
to the vimrc file.

I fixed this by both unifying the handling and inserting common choke
points for the settings.
Support paste to command line

This change will redirect a paste operation when in command line mode.
It will no longer edit the underlying buffer but instead paste to the
command line which is currently in progress

closes #1006
Fix unhandled COMException

During a navigation resulting from a NavigateTo UI, the target
ITextBuffer can fail to provide the set of ITextViews for the buffer.
This was resulting in an unhandled exception.

The point of the method is to return the views if available.  If they're
not available we should just be returning an empty collection.

closes #1013
Fix a typo in command window colors

The background property wasn't binding properly since a recent
refactoring. Related to #949.  Still need to enable VS theming on this
control
CommandMarginControllerTest was failing

The change to enable command mode paste broke this suite because it
added a dependency on ICommandMode being present.  It wasn't enabled in
the mock object and the test failed as a result.
GoTo Definition Tests

Updated the VsCommandTargetTest to include a test for GoTo definition
clearing the active selection
Comment line shouldn't enter Visual Mode

Commenting / Uncommenting out a line shouldn't cause VsVim to enter
Visual Mode.  Right now the editor selects the region even if it's done
on an unselected one.

closes #1014
Home key now a motion

The <Home> key wasn't properly registered as the beginning of line
motion.  In Normal and Visual Mode it wasn't causing any movement to
occur.

closes #1017