added individual pullup setting option to have finer control in case there is a special z-min sensor, for example

Marlin v1

Add M401 - Wait for user to press button on LCD (with optional timeout) minor fix in M115.

repaired thermistortable_6 by graphcial fitting of the off-slope values. see issue 179.  Erik, I know you asked for no changes, but this file probably is not related and hopefully allright. 

Fixed E1_ENABLE pin for Ultimaker. This was wrong for the 1.5.4 and 1.5.3 PCB (I cannot check the 1.5.6)

Marlin v1 - BUG FIXES / CORRECTIONS

Melzi support

Fixes #153 for bad call to abs()