Adding a weighted_degree function to Singular multivariate polynomials

See trac 10716
Use Integer instead of int to avoid overflows
Corrected typo #10716
Ticket: 10716
Make sure that the method works for polydicts.
Do not use ETuples.
#16852: update eclib to 20140805
Merge remote-tracking branch 'origin/develop' into ticket/10716

I'm not really sure why this is necessary, but I was told to do it.
Trac #16852: Upgrade eclib to version 20140805

This version makes default args for friends standard compliant. That
should fix the eclib problem in #12426.

New upstream tarball:
[http://boxen.math.washington.edu/home/cremona/eclib-20140805.tar.bz2].

URL: http://trac.sagemath.org/16852
Reported by: aapitzsch
Ticket author(s): John Cremona
Reviewer(s): François Bissey
Trac #10716: Adding a weighted_degree function to Singular multivariate polynomials

Multivariate polynomials over the Singular interface have several degree
methods but not a weighted_degree function, often used in certain
branches of discrete mathematics. This should be implemented.

URL: http://trac.sagemath.org/10716
Reported by: jsrn
Ticket author(s): Johan S. R. Nielsen, Luis Felipe Tabera Alonso
Reviewer(s): Marshall Hampton, John Perry