Implemented dump and restore functionality for postgres databases. Also added a dropDb function.
Merge branch 'master' into postgres-dump

Conflicts:
	braid/postgres.py
Correcting wrong import
Add some more documentation.
Publish the postgres module as first-level tasks.
Limit exported names (avoid exporting postgres).
Added a temp file context manager
No need to use the postgres user to dump the database
Using the temp file context manager
Removed redundant ---clean argument
Adding means to provide and retrieve the contents of the temporary file from local paths.
Ensuring correct mode
Using the newly introduced functionality for tempfile contents
Allowing to set a user from the command line for dump operations as well.
…and the missing piece of the docum                            …entation.
Use camelCase.
Provide a template to mktemp.

This makes it clear that the tempfile belongs to braid, if it
happens to fail to be deleted, for example.
Put parameters in the same order for dump and restore.