preg_replace() requires quoting, specially for PHP 7.3 (instaclick#91)

Without this, a number of expressions fail (returning NULL),
leading to both non matches and warning/error:

Warning: preg_replace(): Compilation failed: number too big in {} quantifier at offset 6

This is specially noticeable under PHP 7.3, where the new PCRE2 engine
is more picky and has more features, but also may help some cases with
previous PHP versions, depending of the string being searched/replaced.

preg_replace() requires quoting, specially for PHP 7.3 (instaclick#91)

Without this, a number of expressions fail (returning NULL),
leading to both non matches and warning/error:

Warning: preg_replace(): Compilation failed: number too big in {} quantifier at offset 6

This is specially noticeable under PHP 7.3, where the new PCRE2 engine
is more picky and has more features, but also may help some cases with
previous PHP versions, depending of the string being searched/replaced.

Merge pull request instaclick#83 from stof/patch-1

Fix the BC layer for the legacy execute method

Update links

fixes instaclick#81 - completing update to WebDriver W3C Candidate Re…

…commendation 26 September 2017

more tweaks for instaclick#79

fixes instaclick#77 - disable Travis CI functional tests

Revert "Fix: make sure http errors from the requested resource are ca…

…ught and exceptions thrown"

This reverts commit 3b11d17.

Update doc/README

Add curl service example and remove outdated link to upstream wiki page.

Add log types; use official repo URL where possible