Remove camel case limit

[kaveeken]

The existing camel case limit (8) comes from the hard-coded length of SpellerImpl::check_inf. I changed the check function to no longer return when reaching the end of the array, instead reusing the last element of the array for all subsequent checks.

When a CompoundInfo * cpi is passed, reusing ci pointers means cpi->first_incorrect can change as well. Like the current implementation we return, setting cpi->count to zero.

The proposed change means we can accept large camel case words with correct spelling. Providing suggestions for incorrect spellings would require a different approach: making the check_inf array as well as some in suggest.cpp larger (this seems to work with minimal changes) or dynamically sized.

Things I still want to look at/change:

• (re)using a placeholder object separate from the array
• factoring out a check_camelcase function