Support for STM32L1 chips with device ID 0x427

-Changed the STM32L1 "medium plus" (id 0x436) support to be called HIGH.
    -Added the device id 0x427 and call it medium plus.
    -Gave the loader more time so it stopped timing out and thinking it failed.
    -Added st-term to .gitignore

The only controversy (I hope) should be that ST seems to call some chips with 436 medium plus and some high.  It seemed easier to name 436 high and 427 medium plus, so I have changed the 436 support previously here just a bit so get the names to make more sense.