Alteration of standard finger spelling page

[willwade]

Proposed changes to fingerspelling page (nb. I can't recreate the blues etc so ignore the fact the shade is different - where I've used the blue its meant to be the same!):

• pale grey background added to numerical characters like +/ = etc to differentiate from the blank rectangles with white backgrounds above for phrases
   made £ / $ interchangeable on one cell which has enabled me to add in ':' for giving time - I think you would probably only use pounds or dollars, and probably the context would make it clear which one
• moved YES / NO, thereby making space for new 'SPACE' and 'DEL'
• given '@' a pale grey background rather than blue like letters
• moved emojis to make space for YES/ NO, and added a thumbs down one nb. would envisage using the current symbols - just don't have them to hand.

[willwade]

See also #41

[willwade]

@hosseinamin I pretty much did this in the above commits - just aware it probably needs reworking for the new structure