GitLab

i)  There can be two sets of gadgets, one set for page history and another set
    for image history.

ii) There can be one set of gadgets for both settings and two radio buttons to
    select between them.

Only one of these may be present at the same time.  Currently the radio button
version is the one that is in place.  To change to the other version delete the
radio buttons and copy the gadgets from the ChoicesTMP window into the
appropriate window.

Stopped UNIFONT forcing system font use and added calls to Font_WideFormat.
Made sure the system font option is read before fm_init is called!

User agent string now set if Netscape faking is disabled (format used is
"Acorn Browse/1.26 (RISC OS 3.71)".

Minimal support for font choices added, fixed problem with colour changing with browsers with no background colour specified.  Options for Objects implemented.

Choices now allows gadgets to be in any subwindow with some limitations which are addressed in the header file.  Also there is no longer a concept of named subwindows.

Res files had component 0x29fc in frame gadgets for Choices - that's meant to be the 'fake page' display. Sorted that out.

Got rid of unnecessary #define in Choices.h; the gadget autodetect
for the colour choices took its place.

Unsized objects now default to the same dimensions as unsized images.