Gearman: (Ubuntu-variant only) unbroken for 2.x.x series ext

Changes:

• Removed unused git-core PPA
• Added gearman PPA
• Added libgearman8, now required for 2.X.X series extensions
• Added missing runtime extension tests for gearman, not just the package check
• Unbroke the build

Dockerfile: 7.2 package updates, exclusions

• Due to some poorly established PPA dependencies on PHP extension libs, some PHP 7.2 packages may get pulled during non-PHP 7.2 installation. Prevent.
• [PHP 7.2] added missing memcache, memcached, gearman extensions
• [ubuntu] instead of building some extensions from scratch, use newly-aligned packaged versions
• Redis extension: 3.0.2 --> 3.0.3
• [alpine] yaml 2.0.0 --> 2.0.2
• Added missing memcache extension test, where supported
• Test commands now aligned around non-versioned entrypoints

Dockerfile: added bcmath as an extension

Added:

• bcmath extension, enabled by default

PHP 7.2: added back some missing mods

Now that PECL lib has been updated for 7.2, installing from source is now possible

msgpack
igbinary
redis
yaml
apcu

Xdebug: added config switch

Changed:

• Xdebug can be toggled on and off (default) with environment variable CFG_XDEBUG_ENABLE
• Xdebug preconfigured to allow remote debug

Fixed:

• README markdown tag for a header

Breaking: New tagging scheme

In order to account for simultaneously managing multiple supported PHP major/minor combinations, additional tagging granularity is needed.

New Formula:
PHP_MAJOR.PHP_MINOR-Major.Minor.Patch(-variant)

Alpine: added tokenizer extension

Added

• Alpine: includes tokenizer extension

Changed

• Tests for all variants for the tokenizer extension

Alpine: v3.6, PHP 7.1 + cleanup

Changed:

• Ubuntu: removed extra .so files installed via package manager
• Cleaned up after integration test
• Alpine: updated to PHP 7.1 and OS 3.6

NewRelic: removed explicit version lock

Changes:

• NewRelic extension no longer locked to a version. This was important before PHP 7 + 7.1 versions were considered stable, but this is no longer the case.

Dockerfile: upgraded to NewRelic 7.3.1.197

Changes:

• NewRelic changelog: https://docs.newrelic.com/docs/release-notes/agent-release-notes/php-release-notes/php-agent-731197