Big rework of the public api for Sonnet.

Instead of :
Loader::Ptr loader = Loader::openLoader();
loader->settings()->setDefaultLanguage("en_US");
Speller *speller = loader->createSpeller();
if (speller && speller->isMisspelled("word"))
// do something

we'll use:
Speller speller("en_US");
if (speller.isMisspelled("word"))
//do something
which makes babies giggle, women flutter eyebrows and zacks (highly elite set of one) rub their nipples.