Merge tag '4.3.1' into develop

v4.3.1
- initial composer support
Fix: do not version the names of composer packages
New: workaround for PHP 5.3 fatal error when testing
New: restore versioned name for composer package
Further tweaks to address Travis CI failure on PHP 5.3
Fix: Autoloader_Path::emptySearchList() now empties the search list
Version bump
Merge branch 'release/4.3.2'