t:variable should support @mode="text|json|xml|html"

[mpo]

t:variable will already use some clever automatic parsing of input to create the variable (Specially when it is loaded from @src: the mediatype of the received representation will be used to apply some magical parsing corresponding to the type.)

An extra @mode attribute should allow for end-users to override this default media-type driven behavior.

Modes to support:

• text: no parsing leave string as is (cdata)
• xml: perfom xml parsing and return a dom-tree
• html: same but apply nekohtml balancing
• json: parse into java-object

This is in fact a bit of a leftover from #361 (which contained many ideas)

As noted then:

Recent discussion in #358 adds more weight to the idea of having the suggested @mode="text" supported on t:variable too.

Reading json variables from @src and _not_ parsing them ever on the server-side, but simply injecting-transferring them out into the stream seems a common and wanted use case.

[mpo]

(In [1743]) fixes #379
Adding the requested @mode for the t:variant
In a way that it aligns with @mode in t:insert
Some renaming and stuff along the way

[mpo]

comment added to docs about this @mode
​http://docs.outerthought.org/kauri-docs-current/195-kauri/g2/263-kauri.html