Adding an allSelectedText property for custom text to display when every checkbox is selected, and a bShowAllSelectedText boolean property to enabling its use versus the default behavior of showing the selectedText. It defaults to false, so by default the flag is not used to provide backwards compatibility.
Merge branch 'patch-for-all-items-selected-text'

* patch-for-all-items-selected-text:
  Adding an allSelectedText property for custom text to display when every checkbox is selected, and a bShowAllSelectedText boolean property to enabling its use versus the default behavior of showing the selectedText. It defaults to false, so by default the flag is not used to provide backwards compatibility.

Conflicts:
	src/jquery.multiselect.js