Fixed a bug that caused the Interval and Timer extensions and periodic scheduling in general to throw an ArgumentOutOfRangeException when period equaled TimeSpan.Zero.  Includes corresponding unit tests.
Added new portable target PLLITE for net40+sl+8

Added a new target platform PLLITE to create a portable library which
can be used to target more platforms than the current portable build.

Author:    danneesset <daniel.svensson@hotmail.se>
Make it compile for WP7 again

TypeForwardedTo is not availible on WP7
Add example to demonstrate portable library usage
Package Microsoft.Bcl packages
Update build to target net40+sl5+win8+wp8

Add wp8 as supported plaform for PLLITE
SelectMany overloads with index parameter in selector functions.
Added GroupBy and GroupByUntil overloads with a capacity parameter.
Added missing using statements.
Added missing using statement to unit test.
Ran HomoIcon tool.
Merged commit e00c2a7 - pull request from davedev: Added GroupBy and GroupByUntil overloads with a capacity parameter.