storage:support inplace alter table for add/drop column refs #2277
storage:support inplace alter table for alter column order refs #2277
storage:support inplace alter table for alter column rename refs #2277
Merge pull request #12 from naoa/inplace-alter-table-column

support Inplace alter table for add/drop column

Patch by Naoya Murakami. Thanks!!!
test: use meaningful test case name

"rename" is duplicated.
test: add test cases for "ALTER TABLE CHANGE FIRST|AFTER"
storage: fix a bug that "ALTER TABLE CHANGE FIRST" doesn't rename just add
storage: fix "ALTER TABLE CHANGE" implementation

We need to check `ha_alter_info->alter_info->create_list` to find
renamed columns.
storage: add a test case for multiple "CHANGE" in one "ALTER TABLE"
storage test: remove test cases for "ALTER TABLE MODIFY"

Because we don't support it yet.
Revert "storage test: remove test cases for "ALTER TABLE MODIFY""

This reverts commit ce93effd59c0bd2a98a0599df98261c710544cfb.

Because we don't support just "inplace" ALTER TABLE MODIFY.
We support non-inplace ALTER TABLE MODIFY.
storage test: fix group
storage test: add a test case for "ALTER TABLE MODIFY" without order
storage: remove supporting order only inplace alter table

We can't support inplace column date type change.
storage test: use meaningful name
storage test: remove needless group
storage test: add a test case for multiple "ADD"s in one "ALTER TABLE"
storage: use ha_alter_info->alter_info->crate_list to detect added fields
storage test: group "ALTER TABLE DROP COLUMN" test cases
storage test: add a test case for multiple "DROP COLUMN"s in one "ALTER TABLE"