Check系のメソッド名、変数名調整
Merge branch 'pull_req' of https://github.com/cloverlab/cl_echo2 into pull_req

Conflicts:
	ci/application/models/check/CheckCollection.php
	ci/application/models/check/EmptyChecker.php
	ci/application/models/check/IChecker.php
	ci/application/models/check/MultibyteChecker.php
	ci/application/models/check/NumberChecker.php