SWIG wrapper for lmfit

prepared as follows:

$
vi lmfit-ruby.i
swig -ruby lmfit-ruby.i 
ruby extconf.rb
make
#
make install

test:

$
irb
require 'lmfit'
include Lmfit

a = new_doubleArray(3)
doubleArray_setitem(a,0,1)
doubleArray_setitem(a,1,3)
doubleArray_setitem(a,2,5)
Lmfit.lm_enorm(3,a)


def f(t,p)
    return p[0]+p[1]*t
end