In most cases memory deallocation is completely removed from the
code since it can be handled by the default destructor. In a few
special cases a local destructor overrides the default destructor
and makes sure that locally allocated memored is cleaned up correctly.

Move all deallocation from pj_free to pj_default_destructor
Rename pj_latlong.c to fit with the conventional format PJ_latlong.c - freeup was missed here due to wrong naming
Clean up pj_init to avoid double deallocation; Also resolve #576 by adding z_0 and t_0 options in pj_init, while cleaning

Add a prototype for dealloc_params
Added missing errno.h include in pj_ctx.c
Temporarily removing ob_tran from testvarious, to be sure that is where the trouble is
Make PJ_ob_tran.c use proper initialization for the chained projection
proj=ob_tran: make it clear, that we disallow ellipsoidal projections, and, for improved backwards compatibility, turns off default settings, which could inject unwanted ellipsoid definitions
... then also remove the ellipsoid definition from the testvarious test case - which is probably buggy anyway
Work around cs2cs spherical init bug in testvarious; Forbid defs for ob_tran in pj_init

Eliminated mixed code and declarations, converted C++ style comments and
probably did a few more things highlighted by running gcc with the "-W
-Wall -Wextra -pedantic" flags

The brief version::

In an attempt to make proj.4 code slightly more secure and much easier
to read and maintain, I'm trying to eliminate a few unfortunate design
decisions from the early days of proj.4

The work will be *very* intrusive, especially in the PJ_xxx segment of
the code tree, but great care has been taken to design a process that
can be implemented stepwise and localized, one projection at a time,
then finalized with a relatively small and concentrated work package.

The (very) long version: See the comments in PJ_minimal.c