Changed deriving test.
Signature for failure result.

To prevent problems with OverloadedStrings at the use site.
Use primitive modify function in Point instead of primitive set.
Slight code cleanup of abstract lens code.
Lenses are now constructed by providing a modifier.

Not a setter.
Implemented TH deriving code for the new labels.
Renamed Failure to Failing.
Fixed Either labels after merge of 'primitive-modify'.
Probably not true.
Somewhat cleanup the deriving code.
Renamed Maybe to Partial and Either to Failing.

Makes so much more sense.
Cleaned up api+code of the abstract lens module.
Improved documentation failing contexts.
Dericed code now uses ArrowFail instead of ArrowZero.
Fix: Wrong type variable while embedding Either in failing lenses.
Fix: Category identity shouldn't discard the update.
ArrowFail now has Arrow super class, inline with ArrowZero.
Changed some instances of arrow to category.
Start of testsuite.

Removed old tests.
Ignore Data.Label.Derive in HPC reports.

Template Haskell code cannot be coverage checked.