Merge pull request #1 from doncatnip/master

Doncatnip updated
ADD: convert to Boolean validator
Possible mistake pass self argument to bounded method
Remove redundant parentheses
Wrong place for doc string
'compare' var drops out of scope
'val' var does not exist
redundant parentheses
unused value
unused value
unused value
Dev trash cleanup
'klass' first argument to 'cls' replacement
Plural form for child is children
 !!! Api will be changed !!!
Fix val check wrong edit before
Merge pull request #9 from nikitinsm/master

ADD: convert to Boolean validator