Store past versions in git, rather than releases/ directory.

[pserwylo]

In PR #97, it was pointed out that adding autoloading to the composer.json file was not possible because there are two files which specify the same class name. We required the ability to use composer autoloading, and our solution was to:

• Remove the releases/ directory
• Move the contents of releases/2.5/src/ to src/
• Create a commit (5431def) and tag it as 2.5
• Reinstate the contents of releases/3.0/src/ into src/ (but rename the php file to align with that from the 2.5 release so that git notices it is a moved file)
• Rename the file to line up with the file in the old releasles/3.0/src/ and then tag that commit as 3.0.
• Add classmap autoloading to the composer.json

This allows us to specify a dependency on this library from our project like so (in our composer.json):

{
  ...
      "require": {
        "ivt/php-google-map-api": "^3.0"
    },
   ...
}

Note: I'm not sure if tags come through with GitHub PRs. If not, you'll need to create a tag for 2.5 and 3.0 after merging (if you choose to merge this).

Additional Note: This branch also contains a change whereby the composer.json file was changed from streetlogics/php-google-map-api to ivt/php-google-map-api. I wasn't sure if this was required in order to get our fork working or not, but if you choose to accept this PR, let me know and I will change it back to streetlogics in preparation for merging.

[Wilkins]

:+1: