Fix error handlings for fprintf().
Fix error handlings for fputs().
Unify duplicated functions (noregexp() and regexp_check()).
Rename functions for avoinding symbol confiliction.

Add prefix(mrb) to noregexp() and regexp_check().
revert 6c1dfc9; ref #2525 #2565
print lineno of dumping node
adjust node lineno of muiti line statements
Fix mismatches for MRB_API declarations.
git push origin masterMerge branch 'cubicdaiya-issues/declare_mrb_api'
Merge pull request #2570 from cubicdaiya/issues/unify_duplicated_functions

Unify and rename duplicated functions (noregexp() and regexp_check()).
Merge pull request #2572 from cubicdaiya/issues/fprintf_error_handlings

Fix error handlings for fprintf() and fputs() to file.