Added Evaluate pictogram
Merge pull request #2 from wagh/master

Evaluate
simplified code
HomalgExternalRingElement now converts strings to functions

for this it expects a new homalgTable entry called RingElement
LoadHomalgMatrixFromFile now handles finite fields
added Thomas Bächler as author
enhanced InitializeMacros to invoke functions in macro-records
installed \/ for a finite field element and an external ring
installed \in for [ IsRingElement, IsHomalgExternalRingRep ]
fixed \/ for [ IsFFE, IsHomalgExternalRingRep ]

it now takes care of the case DegreeOverPrimeField = 1
added Vinay as author
coding style
added pictograms for Numerator and Denominator
added comment before LeadingModule
host pictogram MonomialMatrix

(outsourced from GradedRingForHomalg v2013.07.14)
installed \/ for external ring element and external ring
fixed a copy/paste bug in previous commit
Always get rid of ranges in homalgCreateStringForExternalCASystem.

Passing a list containing a range to homalgCreateStringForExternalCASystem
results in that range being passed to the external CAS, not the actual list.
Merge pull request #3 from brain0/working

Always get rid of ranges in homalgCreateStringForExternalCASystem.