Merge common files between LPC11XX and LPC11CXX

Based of https://github.com/mbedmicro/mbed/pull/79
Fixed commit message and incorporated feedback by toyowata https://github.com/mbedmicro/mbed/pull/79#issuecomment-25313450

Remaining differences now are
- device.h (DEVICE_CAN 0/1)
- PinNames.h (Currently not accurate for the 11CXX, will fix)
- reserved_pins.h (Should be the same)