added Teng::Plugin::SQLPager
note about inflating and get_column/get_columns
Uninflated value with Teng::Row#_where_cond
added test case. (added inflate/deflate target column to primary key)
added comment for _where_cond
enhanced document for Teng::Schema->instance
fixed pod nesting level
Teng#single should be return scalar value. If it returns empty list, it
confuses user.

e.g.

    $c->render(
        'index.tt', {
            user => $c->db->single('user'),
        },
    );
Merge pull request #88 from nekokak/feature/sql-pager

added Teng::Plugin::SQLPager
Merge pull request #89 from karupanerura/patch/uninflated_value_with_where_cond

Uninflated value with Teng::Row#_where_cond
Merge pull request #91 from nekokak/fix/single-should-return-scalar

Teng#single should be return scalar value. If it returns empty list, it
Rename `_update` to `do_update`. Since some user want to hook _update method.
bar has been added to the table mock_inflate.
adde 'use strict' and 'use warnings' for dumped schema
Merge pull request #92 from nekokak/feature/do_update

Rename `_update` to `do_update`. Since some user want to hook _update method
Merge pull request #93 from karupanerura/hotfix/999_regression_set_column_bug

bar has been added to the table mock_inflate.
Merge pull request #94 from nekokak/feature/dumper-strict

adde 'use strict' and 'use warnings' for dumped schema
Merge branch 'master' of github.com:nekokak/p5-Teng
Do not fail test case when loader.db did not remove cleanly.
Pull up _insert to public api.