Make sure that new migrations is valid, even when there are unavailable
migrations executed.
Update Migration.php

Wrong DateTime format... 'm' is month, not minutes!
Update Version.php

Same error... 'm' instead of 'i' in DateTime version
Fixed the dumping of migration code by escaping PHP strings properly

Fixes #183
Merge pull request #177 from vsmurthy/master

When some migrations are been deleted then 'newMigrations' value is displayed incorrectly
Merge pull request #181 from Jean85/patch-1

Patch 1 - DateTime format trivial error
Major createMigrationTable() performance improvement
minor #75 Major createMigrationTable() performance improvement (dtrethewey)

This PR was squashed before being merged into the 1.0.x-dev branch (closes #75).

Discussion
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Major createMigrationTable() performance improvement

In the createMigrationTable() method in Configuration, the schema is re-created every time the method is called if the migration table already exists.

We were trying to run a fairly large set of migrations across multiple databases and this method is called many times, resulting in lots of createSchema() requests which really slows the migrations down.

Now it's only ever called once per database inside this method greatly improving performance.

Commits
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7ca271b Major createMigrationTable() performance improvement
Merge branch 'master' of https://github.com/doctrine/migrations