Update version string to 2.5.1-pre.1
Update version string to 2.5.1-pre.4
BHV-12479: Fix SlideableSample, remove FlexLayout

Fixed a minor bug in SlideableSample and removed the never-
officially-released FlexLayout.

Enyo-DCO-1.1: Signed-Off-By: Gray Norton (gray.norton@lge.com)
Merge pull request #100 from enyojs/BHV-12479-graynorton

BHV-12479: Fix SlideableSample, remove FlexLayout

Reviewed-By: Cole Davis (cole.davis@lge.com)
Update version string to 2.5.1-pre.6
Merge branch 'master' into ENYO-12

Conflicts:
	flex/source/ResponseStrategies/kind.ResponseStrategy.js
	flex/source/ResponseStrategies/kind.RowAfterColumns.js
	flex/source/enyo.Styles.js
	flex/source/kind.ContentLayout.js
	flex/source/kind.FlexLayout.js
	flex/source/mixin.LayoutInvalidator.js
	flex/source/package.js
	version.js