updated docs, bump vers (cltk#575)

mk api updates, bump vers

bump vers

Regex lemmatizer update (cltk#565)

* Refactor RegexpLemmatizer

* Update Regexp Lemmatizer test

* Update Regexp Lemmatizer test

* Refactor RomanNumeralLemmatizer

* Add test for BackoffLatinLemmatizer; fix test coverage in general

bump vers for arabic

Fix some Arabic mistakes during coding (cltk#552)

* Add classical arabic corpus and all arabic letters/symbols

* transfer ownership corpuses to cltk

* transfer ownership corpuses to cltk

* update corpus/arabic/corpora.py

* added arabic word tokenizer

* mk pyarabic optional install

* replace if with elif

* fixed line 16 corpus/arabic/alphabet.py

* added arabic stop words

* ch print to log

* Added blank line

Add line tokenizer to CLTK (cltk#530)

* Add line tokenizer with tests

* Fix line tokenizer return

* Update docs to include line tokenizer

* Fix code block in docs

replace long_description in setup to fix install error

bump vers to 43

bump vers for oe fix