relax SVN archive

A warning system for relax.

This is based on the system started in r2532, and is discussed in
detail in the thread starting:
https://mail.gna.org/public/relax-devel/2006-08/msg00071.html

The system is based on the standard Python warnings system.
Warnings are generated with the syntax:

warn(RelaxWarning(args))

where RelaxWarning can be any of the Warning classes defined in
errors.py, and args is an arbitrary number of arguments of
arbitrary type which are used by the Warning class to generate a
meaningful message string.

The system also impliments a --pedantic command-line flag, which
causes all warnings to be escalated to exceptions. All of the
relax warnings are subclasses of both BaseWarning and BaseError,
so the escalated exceptions will be caught by except clauses
based on these types.

A further feature in the current implimentation is to include
an exception-like traceback in the warning message when in
debug mode.

Creating a new branch for work on the RelaxWarnings system

See discussion in thread starting:
https://mail.gna.org/public/relax-devel/2006-08/msg00071.html

Rolling back revisions 2535-2537

See discussions in the thread starting:
https://mail.gna.org/public/relax-devel/2006-08/msg00052.html

Modified the sys.exit() statements to return 1 to the shell to indicate failure.

Significant improvements to the new error/warning system.

The idea of this system was suggested in two threads which commence at:
https://mail.gna.org/public/relax-devel/2006-08/msg00052.html
https://mail.gna.org/public/relax-devel/2006-08/msg00053.html

The improvements includes the addition of the printing of the traceback, the option of saving the
program state (self.relax.data pickling), a new way of calling the RelaxErrors or RelaxWarnings
(for example RelaxBadError('Hello')), addition of the warning functions, and a number of other small
changes.

Start of a new relax error/warning subsystem.

The idea of this system was suggested in two threads which commence at:
https://mail.gna.org/public/relax-devel/2006-08/msg00052.html
https://mail.gna.org/public/relax-devel/2006-08/msg00053.html

Essentially a rudimentary framework for replacing the entire Error and Warning system has been set
up. Many essential elements are missing (for example the warning function, tracebacks, etc)
however it shouldn't take long to add these. This new system significantly simplifies the
RelaxError/RelaxWarning system, allows easy implementation of the --ignore-errors and --pedantic
command line flags (https://mail.gna.org/public/relax-devel/2006-08/msg00052.html), and allows fine
tuning of how RelaxErrors and RelaxWarnings are handled within the different relax user interfaces
(UIs).

Janitorial changes to r2533

As discussed on relax-devel at gna dot org:
https://mail.gna.org/public/relax-devel/2006-08/msg00055.html

Alterations to the debug mode.

These changes reflect the discussion on relax-devel at gna dot org:
https://mail.gna.org/public/relax-devel/2006-08/msg00049.html

Two functions are implimented when in debuging mode:
1) KeyboardInterupt during script execution will print the normal
python traceback
2) The all of the relax exception classes will save the program
state

Created the RelaxWarning subsystem. The standard 'RelaxWarning' and the 'RelaxZeroVectorWarning'
warning classes have been created.

Modification of proposed fix to bug #6503

Based on discussion on relax-devel at gna dot org:
https://mail.gna.org/public/relax-devel/2006-08/msg00033.html

This modification does not raise RelaxError if the amide bond length
is 0, but rather sets the bond vector to None