Merge pull request #5 from alinadubatovka/master

Gist::search() implementation =^.^=
Merge pull request #6 from alinadubatovka/master

Non-recursive Gist::search() and Entry::getChildren() instead of Entry::find() =^_^=
Gist::insert() is implemented with some private methods
bugs fixed: build
pointer to ParentEntry is added into inner_Entry and inner_Entry::getSubpredicates() is added to get predicates of children entries for Gist::split()