changed content-wrapper calc() from `%` to `vh` & added content-wrapper calc() with collapsed header

Updated version info in the footer and changed copyright text to the current one.

- changed height: 0px to height: auto for uk.treeview-menu to fix not smooth treeview closing
- fixed .content-wrapper calc, it returned -2% before
- changed order of js file generation
- rebuild dist files

- changed github links to ColorlibHQ
- removed Donations part

- updated repository url in package.json
- updated copyright infos for js in Gruntfile.js
- updated copyright infos for css in AdminLTE.less & AdminLTE-without-plugins.less
- rebuild dist files

- added code from #2001 thanks @CoderSquirrel

Closes #1854 & #2001

- updated ControlSidebar.js to hide control sidebar instead of only moving it
- updated dashboard.js to use containment in sortable()
- added display none to control sidebar content in index.html

(Closes #1924)

Closes #2027

Update adminlte.js

Fixing bug throwing error "Uncaught ReferenceError: expandingEvent is not defined" when collapsing .box .

Fix layout skin-black-light height inconsistence

Treeview expand

Fix typo which breaks BoxWidget collapsing.