netteForms.js: getValue returns always arrays for multiple selectboxes
tests: skip tests when pdo_sqlite extension is missing
Travis: start memcached server explicitly
Dumper, Neon: var_export(float) replaced with json_encode(), because var_export uses serialize_precision since PHP 5.5.6/5.4.22 [Closes #1273][Closes #1277]
netteForms.js: toggles are attached only on 'changed' event [Closes #1087]