Merge pull request #888 from edx/fix/ichuang/add-capital-greek-to-formulaequationinput

formulaequationinput: add capital greek letters and hbar to calc preview

common/lib/calc/calc/preview.py

@@ -113,6 +113,12 @@ def enrich_varname(varname):
              "vartheta iota kappa lambda mu nu xi pi rho sigma tau upsilon "
              "phi varphi chi psi omega").split()
 
+    # add capital greek letters
+    greek += [x.capitalize() for x in greek]
+
+    # add hbar for QM
+    greek.append('hbar')
+
     if varname in greek:
         return ur"\{letter}".format(letter=varname)
     else: