Implement Decorator functionality

[mspaulik]

Try out usage of different decorators:

• deprecated
• doc - attach a documentation string. Works great with multiline string literals.
• summary - attach a documentation string. Typically a short single line description.
• format - specify the data format hint for a string type.
• pattern
• knownValues - make a string type with an enum that contains all known values.
• secret - make a string as a secret value that should be treated carefully to avoid exposure.
• minLength/maxLength
• minValue/maxValue

[mspaulik]

DONE:
minLength/maxLength
minValue/maxValue
doc - attach a documentation string. Works great with multiline string literals.
summary - attach a documentation string. Typically a short single line description.
deprecated
pattern
secret - make a string as a secret value that should be treated carefully to avoid exposure.
format - specify the data format hint for a string type. (done on andImplementation branch)
knownValues - make a string type with an enum that contains all known values.
Custom decorators