HPCC-9936 Add option --keywords to eclcc to create xml list of reserved ...

...words

Signed-off-by: jamienoss <james.noss@lexisnexis.com>
This contains two distinct items (although there is some overlap)

1. scalar functions that can be used in any expression e.g.,
eckcrc hash, matchlength, [sizeof]

2. attributes which can go on specific activities
- the majority

You would generally want these to be coloured differently