Solve escaping issues with difficult py file commands

[komlenic]

In particular, see node.drush_sql() which is only necessary to accommodate difficult sql commands that must be able to execute correctly locally and remotely (over ssh).

The present drush_sql command applies different levels of escaping to a query, and does appear to work, but this should be better understood and accommodated if possible.

Complicating this issue is a chain of escaping that goes through: python, fabric, shell, and drush.

[komlenic]

The present handling of this requires that the string literal passed to drush_sql() must be triple single quoted, and have all single quotes escaped with . Double quotes within the string literal should be passed unmodified.