Switch to the post search engine using the new PostQuery parser. The new
engine fully supports AND, OR, and NOT operators and grouping expressions
with parentheses.
Highlights:
New OR operator:
* `skirt or dress` (same as `~skirt ~dress`)
Tags can be grouped with parentheses:
* `1girl (skirt or dress)`
* `(blonde_hair blue_eyes) or (red_hair green_eyes)`
* `~(blonde_hair blue_eyes) ~(red_hair green_eyes)` (same as above)
* `(pantyhose or thighhighs) (black_legwear or brown_legwear)`
* `(~pantyhose ~thighhighs) (~black_legwear ~brown_legwear)` (same as above)
Metatags can be OR'd together:
* `user:evazion or fav:evazion`
* `~user:evazion ~fav:evazion`
Wildcard tags can combined with either AND or OR:
* `black_* white_*` (find posts with at least one black_* tag AND one white_* tag)
* `black_* or white_*` (find posts with at least one black_* tag OR one white_* tag)
* `~black_* ~white_*` (same as above)
See 4c7cfc73 for more syntax examples.
Fixes#4949: And+or search?
Fixes#5056: Wildcard searches return unexpected results when combined with OR searches
af183467b6