Add support for injecting regex engine with its options on startup in a bootstrap option. These are some API, runtime and implementation changes.
* google_re2 in safe_regex will be deprecated and no longer be required. Regex::parseRegex will choose the registered regex engine to parse expressions into matchers.
* A new bootstrap option default_regex_engine will be introduced for regex engine selection.
* For compatibility, GoogleRE2 will be chosen as default regex engine if no regex engine is designated.
Signed-off-by: Xie Zhihao <zhihao.xie@intel.com>
Mirrored from https://github.com/envoyproxy/envoy @ 0a92cc86e7f8b88d5af0eb2e27b5c7ef64719e56
data-plane-api(Azure Pipelines)