remove unnecessary depedency in test build
use macros for assignments to ci->err
mrb_ary_splat() to call #to_a
Merge pull request #1639 from h2so5/macro-ci-err

use macros for assignments to ci->err
Merge branch 'master' of github.com:mruby/mruby
quicker release of arena after ensure calls
always clear ci->err
pop ensure stack before execution; close #1638
should splat and iterate elements when "*ary" speficied in the case-when clause; close #1627
object_id may not return Fixnum (ISO says Integer), since intptr_t may be bigger than Fixnum, so type check for Numeric; ref #1630
Test case statement with splat
Merge pull request #1640 from carsonmcdonald/splatwhentest

Test case statement with splat
execute ensure clause correctly without OP_EPOP
avoid decrimenting eidx out of ecall()
need not to initialize ci->err at toplevel
Test for raise in ensure
Merge pull request #1643 from take-cheeze/remove_unnecessary_depedency

Reduce unnecessary mrbgems full test rebuild.
Merge pull request #1644 from carsonmcdonald/testraiseinensure

Test for raise in ensure
tests for "case" expression.
adjust proc->target_class according to surrounding proc->target_class; based on a patch from @Fleurer; close #1627