Merge pull request #37 from blazetopher/fix_bounds_update

Fixes bounds update when value is scalar
Fixes bug in _update_min_max
Merge pull request #38 from blazetopher/fix_minmaxupdate

Fixes bug in _update_min_max
Moves most functions to AbstractCoverage; First impl of ViewCoverage

Migrates almost all functions to AbstractCoverage for reusability and simplicity

First implementation of ViewCoverage - parameter filtering

Conflicts:
	coverage_model/coverage.py
Fixes minor bug with examples.ptypescov()
Makes first pass at ComplexCoverage

First ComplexCoverage implementation for ComplexCoverageType.PARAMETRIC
Fixes all str checks to use basestring
Fixes test group for param_func tests
Updates to ComplexCoverage

Adds loading support

Renames ViewPersistenceLayer -> SimplePersistenceLayer and utilizes for
both ComplexCoverage and ViewCoverages
Adds ComplexCoverage example for SBE_37IM

Example creates 2 SimplexCoverages (Time, Lat, Lon) and (Time, L0 params) and a ComplexCoverage that references both and provides the L1 & L2 params
Updates SimplePersistenceLayer with data bounds
Merge pull request #39 from blazetopher/refactor_coverage

Refactor coverage
Modifies method by which bricks are managed.  Initial trial.

Creation seems to be working, loading does not.
Migrates brick metadata to master file.
Adds read_only flag to ParameterManager
Adds sharing of domain objects

Adds _assign_domain function - allows ParameterContexts added to a coverage to share the temporal and spatial domain objects of the coverage, rather than just the extents information.

Also allows _assign_domain to be called during load to ensure ParameterContexts use shared domain objects after reloading a coverage
Isolates creation of virtual bricks from each parameter initialization.

Many log.warn added, must be removed in future commit.
Removes references to parameter_name in the brick_list.
Changes order of MasterManager initialization of the brick_tree.
Updates insert_timesteps to call expand_domain only once.  Fixes method by which external links are added to the master file.

Reverts test_coverage_basics.test_create_multi_bricks to not use a parameter name.