Add --skip-welcome-message

Also update peerDeps
Save user configuration

Prompt will be asked on first use and save to
.yo-rc.json. Currently this file need to edit manually
(or remove) for new Assemble scaffold prompt.

Once the manual edit is done, just run yo assemble to
scaffold the project.
Change prompt type from list to checkbox

Allow user select multi plugin. Enable permalinks
and sitemap plugin by default.

Ref: #17
Fix plugin generator in package.

Add simple funtion to normalize package and force overwrite.
Assemble Plugin Generator

yo assemble:plugin -h or See
[Usage](https://github.com/assemble/generator-assemble/tree/master/plugin/USAGE)

Fixed #17 and closed assemble/grunt-init-assemble-plugin#1
Add assemble-plugin as prefix
Fix template conflict between Yeoman and Grunt
Fix gruntfile template
Merge branch 'grunt-yeoman-conflict' into dev

Conflicts:
	app/index.js
	app/templates/Gruntfile.js
Default install plugin
Fix task not found

Remove load-grunt-task and fix gruntfile for plugin.
I'm confuse how to use it. Ref: #16

Close #18
Various fixes

 - Change homepage
 - Remove unused code
 - Fix preset for permalink
Add .yo-rc.json to gitignore template
Update docs and bump version
Merge pull request #19 from hariadi/dev

Support Assemble Plugin