[TASK] Shift to internal recursive array merge in inheritance
[TASK] Expand returned field array to variable then return
[FEATURE] Finer inheritance settings on every Flux field type

This feature adds two new attributes to every Flux field:

* inherit (integer, used only as boolean currently)
* inheritEmpty (boolean)

Setting these attributes will affect how each field is processed when parsing the root line of records that make up an inheritance tree. By setting `inherit="0"` you can prevent the particular field form inheriting its value - and by setting `inheritEmpty="TRUE"` you can allow empty (but non-zero) values to be inherited.

The reason for always allowing inheritance of a true zero value is that this particular value is often used as a "none" value rather than a value which should be overridden by a parent value.

Fixes: #36
[TASK] Allow zero to be considered non-empty in inheritance
[BUGFIX] Don't think an integer is a boolean
[BUGFIX] Use correct name "inheritEmpty" when reading value
[TASK] Avoid empty field when saving empty sheets
[FEATURE] Property "clear" (boolean) on every Field ViewHelper

Setting this property to TRUE displays a "clear value" checkbox next to the field. Checking this box completely destroys the value.

Must be manually specified for fields which should support such behavior.
[FEATURE] Attributes maxSize and disallowed on file field
[TASK] Split error handling in AbstractFluxController to reusable method
Merge pull request #124 from NamelessCoder/fileattributes

[FEATURE] Attributes maxSize and disallowed on file field
Merge pull request #126 from NamelessCoder/errorhandling

[TASK] Split error handling in AbstractFluxController to reusable method
[BUGFIX] Fix fatal error using extensionName without custom controller
[TASK] Use class constant to store specially treated Exception code
Merge pull request #127 from NamelessCoder/errorhandling

[BUGFIX] Fix fatal error using extensionName without custom controller
[TASK] Remove unused argument in FluxService
Merge pull request #128 from NamelessCoder/unusedserviceargument

[TASK] Remove unused argument in FluxService
[BUGFIX] Inconsistent assignment of template variables

This fixes an issue with variables which are resolved to be inserted in the View. Before, variables would never contain the ones defined in the flexform. After, the flexform variables are used if they contain a "settings." prefixed array.

Fixes: https://github.com/FluidTYPO3/fluidcontent_bootstrap/issues/37
Fixes: #121
[TASK] Remove superfluous, repeatedly sent debug message
[DOC] Fix doc comment block in AbstractFluxController