page-optimize

Prior to this change, we cached all headers sent before the concatenation
service responds. In most cases, that would be fine because the service
responds very early to the request, but it is technically possible for
another sensitive header to be added prior to response and cached
for sharing with other requesters.

This change removes that possibility by only caching a specific set of
headers.

Which we should've done with the commit that
made service.php WP independent.

Catch child themes of Divi too.

Breaks a bunch of stuff, not easy to debug. Treat as we're in wp-admin.

To increase performance, we are updating our concat service to run without loading WordPress. For this to work, we need to provide real FS paths to the concat script rather than WordPress URIs that need WordPress constants to properly resolve.

By default, we will continue to resolve WordPress resource URIs in the concat service, but we will work from real FS paths when the following constants are defined.

Use the correct FS resolution function. Wasn't resolving to anything, so no cache busting
appended for single files.

We submitted this to the plugin directory and received helpful critical feedback.

The plugin doesn't resolve the locations of JS and CSS files in a way that will work with all WordPress installations. The purpose of this PR is to resolve that issue.

Code refactoring to reduce duplication.

• WP Cron job for cleaning up cached files older than 24 hours. They get regenerated on next request after cleanup.
• Default JS load mode to none. Since we don't defer all the scripts, it breaks a lot of plugins.
• Purge options on plugin uninstall.

Customizer is giving us headaches. Just skip optimizations if we detect it.

Forgot to create all subdirs, so it fails.

• Default values on activation. Wrapped in functions, so easy to change
• Exact match exclusion list, instead of finding a substring
• implode() was used incorrectly

Improved DOM interactive time by a huge margin, because of the exact match excludes. :)

Bump to 0.1.0 before release.

• Add default caching directory

This release also contains:

• Bug fixes
• Improved settings page appearance

This release adds optional local caching for testing purposes and eventual use from the .org plugins repo. It does not currently support cache cleanup.