Search addon: Support "match whole word" option

[Tyriar]

When true, a search for "term" would match "a term b" but not "a terms b"

Plan issue: #705

[alexr00]

It seems like space wouldn't be the only delimiter that signifies the start/end of a word. I'm thinking that anything that isn't a letter or number should be used as a "whole word delimiter".
Examples where "term" would not match:
"a 5term b"
"a term2 b"
Examples where "term" would match:
"a %term b"
"a (term} b"

[Tyriar]

@alexr00 👍 I think this is what monaco does as well.