ACD changes for 2.9.0

[Peter Rice]

Just committed some new ACD validations (in acdvalid). Interface 
developers will need to look for them in 2.9.0.

New section "additional" for qualifiers with additional:"Y" defined.
I would suggest treating this in the same way as "advanced" (for many 
programs it needed only a rename of the advanced section).

New ACD type "toggle" - this is the same as "boolean" and will be used 
for thoe boolean values that are only used to control other ACD 
qualifiers (-plot for example). acdvalid will allow these toggles in 
other sections, and will (but not yet) check for them in calculated 
values. Boolean values will be expected to appear in the required, 
additional or advanced sections (but can be in the input or output 
sections without problem, as before).

Input and output datatypes now must appear in the input and output 
sections. matrix, datafile and cfile datatypes have been relocated.

The application name in the ACD file must match the true application 
name. This is only checked by acdvalid so far to avoid breaking 
third-party ACD files.

Output outfile, align, report, etc. have new attributes:

nullok - if true, can return a NULL value

nulldefault - if true, defaults to a NULL value. Setting a filename on 
the command line overrides and creates an output file. Setting to "" on 
the commandline ***creates the expected default filename***

missing - if true, can ctreate the expected filename by simply using 
-qualname on the commandline (rather than -qualname="") if it is last on 
the command line or followe dby anotehr qualifier (if followed by a 
paraneter that will appear to be the filename value)

I have started to change "string" datatypes to other datatypes if 
approporiate (for example to directory or datafile). There will be more 
of these.

Peter