BUG: Fixed exclusion list

Currently iris test coding standards will perform pep8 checks on files
contained within the build directory and then ignore the results.  This
commit removes this checking entirely and fixes a bug present in
generating the assumed directory for the iris repository from the iris
path (a problem which arises when considering softlink vs real paths).
First draft of testing guidelines
Second draft
Fix typo
Support masked arrays in broadcast_to_shape.
Added unit tests for rolling_window function.
seems to be working
updated
looks like its working
working name tests
fix test
Slight refactor
Review actions completed
Completed review actions.
Merge pull request #826 from cpelley/name_vertical_levels

Name vertical level interpretation
Added land compressed PP/FF file loading.
Review actions.
First review actions from rhattersley.
Last review actions from rhattersley.
Merge pull request #825 from pelson/land_packed_UM_fields

Added land compressed PP/FF file loading.