added isTree/isBlob method to Git\Object.
added isTree/isBlob method to Git\Object.

this method is useful in determining whether any type of Git\Object.

[before]
$tree_entry->toObject()->getType() == Git\Object\Tree

[after]
$tree->entry->toObject()->isTree() / isBlob()

perezvon, thanks for your advice.

MagicalTux/php-git,garvins/php-git,MagicalTux/php-git,libgit2/php-git,libgit2/php-git,garvins/php-git,garvins/php-git,libgit2/php-git,garvins/php-git,MagicalTux/php-git