`LIKE` escape sanity:

* Deprecate `like_escape()`
* Add a method to `$wpdb`, `->esc_like()`, and add unit tests

`$wpdb::esc_like()` is not used yet. As such, many unit tests will throw `Unexpected deprecated notice for like_escape`. Subsequent commits will alleviate this.

Props miqrogroove.
See #10041.

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git-svn-id: http://core.svn.wordpress.org/trunk@28527 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Replace all uses of `like_escape()` with `$wpdb->esc_like()`.

Props miqrogroove.
See #10041.

Built from https://develop.svn.wordpress.org/trunk@28712


git-svn-id: http://core.svn.wordpress.org/trunk@28528 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add a `$run_texturize` static var to `wptexturize()` that is filterable via a new run-once filter: `'run_wptexturize'`. Allows user to disable texturization.

Needs filter docs.

Props nacin, SergeyBiryukov.
See #19550.

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git-svn-id: http://core.svn.wordpress.org/trunk@28529 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Ensure that `shortcode_unautop()` treats `&nbsp;` like whitespace.
`shortcode_unautop()` and `wptexturize()` now use `wp_spaces_regexp()` instead of raw regex.

Adds unit tests.

Props miqrogroove.
See #27588.

Built from https://develop.svn.wordpress.org/trunk@28716


git-svn-id: http://core.svn.wordpress.org/trunk@28530 1a063a9b-81f0-0310-95a4-ce76da25c4cd
`smilies_init()`, treat `&nbsp;` like whitespace when converting smilies.

Adds unit tests.

Props miqrogroove.
Fixes #27587.

Built from https://develop.svn.wordpress.org/trunk@28717


git-svn-id: http://core.svn.wordpress.org/trunk@28531 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `wptexturize()`, treat `&nbsp;` like whitespace when texturizing hyphens.

Adds unit tests.

Props redsweater, miqrogroove.
Fixes #23185.

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git-svn-id: http://core.svn.wordpress.org/trunk@28532 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `wptexturize()`, don't convert C-style hexadecimals to mathematical `×`.

Adds unit tests.

Props harrym, kurtpayne, miqrogroove.
Fixes #19308.

Built from https://develop.svn.wordpress.org/trunk@28719


git-svn-id: http://core.svn.wordpress.org/trunk@28533 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `WP_Comment_Query::get_search_sql()`, don't double-like-escape.

Props miqrogroove.
See #10041.

Built from https://develop.svn.wordpress.org/trunk@28720


git-svn-id: http://core.svn.wordpress.org/trunk@28534 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix curly quotes around numbers when applicable.

Adds unit tests.

Props filosofo, mrmist, aliso, MikeHansenMe, miqrogroove.
Fixes #8775.

Built from https://develop.svn.wordpress.org/trunk@28721


git-svn-id: http://core.svn.wordpress.org/trunk@28535 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Set a variable for like-escaped string before looping in `WP_User_Query::get_search_sql()`. 

Props miqrogroove.
Fixes #10041.

Built from https://develop.svn.wordpress.org/trunk@28722


git-svn-id: http://core.svn.wordpress.org/trunk@28536 1a063a9b-81f0-0310-95a4-ce76da25c4cd