Place Postgres upgrade schema sql files here.

File name:

X.sql, where X is the Postgres schema id

Example:

'9.sql' file is read by FogLAMP app which has Posgres schema version set to 8
'10.sql' file is read either by FogLAMP app which has Posgres schema version set to 9
either by FogLAMP app upgrading schema from 8 to 10

Note:
- whenever VERSION file in $FOGLAMP_ROOT has a new schema in 'foglamp_schema',
  the corresponding sql file must be placed here
- file id must exist even if empty

