Update to 1.13.

Version 1.13

  * Fixed templates lookup name syntax errors reported by Brandon
    Invergo <brandon@invergo.net> (detected by compiler g++-4.7).
    Many thanks for your patch, Brandon.

  * Fixed a bug reported by Jacques Beilin <jacques.beilin@ensg.eu>

    Function NormalDistribution ended in an endless loop for high
    values of input argument x.

  * Fixed a bug reported by Anton Horpynich <anton@vingeo.com>

    The computation of approximate coordinates failed if an angle
    needed for computing of an intersection was smaller than 0.15
    radians / 10 gons (implicit testing criterion). Although this is a
    reasonable limit for standard surveying networks, in a batch
    computation of approximate coordinates a much smaller value can be
    sometimes acceptable. It is more or less a matter of personal
    opinion if this is to be supposed a bug or not.

    Gama newly solves approximate coordinates in two main loops.
    During the first loop the default value 0.15 in class Acord is
    used.  If afterwards there  still some coordinates remain
    missing, Gama starts a second loop with series of iterations in
    which firstly tries to find a solution with the default value
    then secondly with a very tiny limit of 0.0015 radians.

    In most cases all coordinates are solved in the first loop with
    the default small angle limit 10 gons.

  * In gama-local suppressed output of running results during
    linearization iterations and several other minor fixes

Version 1.12

  * class BaseVisitor and related classes moved to separete file visitor.h

  * local Observation has protected init method and non-parametric constructor
    Code in local Observation was reorganized and some atributes are not const.

  * local observations are visitable (base is Accept<>)
          -  class Direction : public Observation
          +  class Direction : public Accept<Direction, Observation>
      ** local observations' write methods moved to WriteVisitor
      ** LocalRevision and LocalLinearization are now visitors
      ** base classes Revision and Linearization removed from local
      ** method observations_summary in LocalNetworkXML uses visitor for counting
      ** method observations in LocalNetworkXML uses visitor for writing
      ** function OutlyingAbsoluteTerms uses visitor for writing
      ** method test_abs_term in LocalNetwork uses visitor for test
      ** local Observation set_passive and set_active methods are now non-const
      ** function AdjustedObservations uses visitor for writing part of table row
      ** function TestLinearization uses visitor for computing and writing
      ** function ResidualsObservations uses visitor writing observation name

  * fixed a bug in the definition of angular observations reported
    by Anna Kratochvilova <anna.kratochvilova@fsv.cvut.cz> and Vaclav
    Petras <vaclav.petras@fsv.cvut.cz>

  * updated version of review.hu.lang by Siki Zoltan, some
    corrections in the Hungarian translation of GNU Gama

(gdt)