Add support for Excerpts

Added support for Excerpts and added sample template for using them for
read more functionality
More excerpt sample into OneColumn theme
Add excerpt editing to TwoColumn and OffCanvas
Merge pull request #95 from sbulluk/master

Add support for Excerpts
Fixed a bug where the excerpt div didn't show when creating new posts.
Merge pull request #96 from fredrikeriksson/excerpt-fixes

Fixed a bug where the excerpt div didn't show when creating new posts.
Merge branch 'master' of https://github.com/madskristensen/MiniBlog

Conflicts:
	Website/scripts/admin.js