Generate Phar file for Analyzer tool, for easier distribution.

[dave-newson]

Add the ability to build the Analyzer command as a phar file: meminfo.phar

The meminfo.phar file can be built using ./bin/build-phar.sh as part of a release.

The build script will;

• pre-clean the build dir
• Install the Vendor dependencies,
• Install "Box" for phar packaging
• Create meminfo.phar using Box.
• Create an sha256 hash for meminfo.phar

Supplying a Phar file makes it a lot easier to use the Analyzer tool, instead of having to download and install the repo, as either a global or isolated dependency.

Box version is locked to be compatible with PHP 7.2 as this was the environment I had available.