add more functional array props for struct

[jimdebeer]

essential for jsx

• [x] find
• [x] findIndex
• [x] slice
• [x] sort (but immutable)
• [x] every
• [x] values
• [x] some
• [x] indexOf
• [x] lastIndexOf
• [x] reverse
• [x] includes

[jimdebeer]

opt chains ins jsx make a 'chainable' to not create too many new ones