Correct entries in thermocouple lookup table (entry for 64C was noticeably off and would cause a 2C error; other values were rounding issues).  Add reverse lookup for converting cold junction temp to mV (scaled into adc counts of 32767/256).  Perform t/c temp conversion using industry standard method of measure cold junction temp, cjt; convert cjt to a mV reading compatible with t/c type; convert sum of t/c mV reading and cjt in mV to temp.  MBI was converting t/c mV to temp and then adding that temp to cj temp; that can cause errors of up to ~0.8C.  While for 3D printing that's okay, it's nice to use the same methodology for when comparing external temp reads to what the bot reports
Disable modified cold junction handling for now; leave for further testing
Merge pull request #53 from jetty840/dcnewman-merge

Dcnewman merge