Embedded OpenSans Font and create Common Font Variables in DynamoModern.xml
Change current font to Embedded OpenSans for all UI control in DynamoView window

Conflicts:
	src/DynamoCore/UI/Views/DynamoView.xaml
New Dark Theme UI for all control such as Button, Textbox, Checkbox, Dropdown
Implemented PreferenceSettings

Settings that became persistent:
1) Show Console
2) Connector Type
3) Fullscreen Watch Mode

Test cases included
Improvement on UI Textbox Watermark behavior
Merge remote-tracking branch 'upstream/ChocoButter' into ChocoButter
Merge pull request #750 from l2obin/CherryPickEmbeddedFontFeature

Cherry pick features from ChocoButter to ChocoButterUI
Merge remote-tracking branch 'upstream/ChocoButter' into ChocoButter
MAGN-728 Fixed Zoom is not working (using scroll) after opening attached file.

Issue: EndlessViewModel didn't take X and Y into consideration at the start.
Opening save file can start at the "saved position" for the workspace.
MAGN-701 Fixed "New workspace does not start at it's offset and zoom"

Issue: Newly created WorkspaceView's offset and zoom is not based on its WorkspaceModel's attributes.

This issue causes shortcut function of pan or zoom to jump. As those function make use of
WorkspaceModel's attributes for its operation.

It also causes EndlessGrid to appear at the wrong position, causing infinite canvas feature to fail.

This commit fixes them.
MAGN-687 Fixed canvas manipulation interface not working in Custom node workspace
Merge pull request #756 from l2obin/CanvasControlFixes

Fix for MAGN-687, MAGN-701, MAGN-728
Merge remote-tracking branch 'upstream/ChocoButter' into ChocoButter
Merge branch 'ChocoButterUI' of https://github.com/ikeough/Dynamo into ChocoButterUI
Refactored fade in and fade out to view instead of performing it in view model.
Merge remote-tracking branch 'upstream/ChocoButter' into ChocoButter
Removed a redundant raisepropertychange which appears to be solving the preview disappearing issue.
Merge pull request #760 from SkyApple/PreviewDisappearingFix_ChocoButterUI_BugFix

Fix for node preview disappearing after multiple collapse+expand
Fix broken test cases
Move AST nodes compilation to main thread to avoid node state contention