Use toString function in README

This helps illustrate that the uuidX() functions return Uuid objects,
and not strings.
Set the default timezone to avoid errors in hhvm

Added a default timezone to the bootstrap.php to fix errors in HHVM
tests, which was introduced when Travis removed the default `/etc/hhvm/php.ini`
in https://github.com/travis-ci/travis-ci/issues/2523#issuecomment-59303763
Exclude build/development tools from releases using .gitattributes
Set timezone for tests
Merge pull request #35 from jwpage/doc_toString

Use toString function in README
Merge pull request #37 from fisharebest/gitattributes

Exclude build/development tools from releases using .gitattributes
Bumping the version number to 2.7.4
Setting version in master to 2.7.x-dev
Auto-generated changes to apigen.neon by apigen-4.0.0-RC3
Add support for MS GUIDs
Remove non PHP 5.3 syntax
Set default timezone in PHPUnit bootstrap to pass HHVM tests
Merge branch 'master' of github.com:aztech-digital/uuid