Add Support for STM32L1xx Medium Plus and High density Devices

	Using reference RM0038 Rev 7
		The flash size register moved
		and the values in the registers changed their meaning
		Note that Medium Plus and High density deives have the
		same device ID, but only the Medium Plus definition is
		used in the code (the High comes along for free)
Merge pull request #140 from mower7/master

Adding Support for STM32L1xx Medium and High density devices