Add ability to provide generic configuration parameters for the JIRA Macro

Goal: Offer configuration parameters for JIRADisplayer, JIRAFieldDisplayer or JIRADataSource component implementations.

Use case example: Give the URLJIRAFieldDisplayer the ability to configure the link label used.

Implementation details:

• Introduce a JIRAMacroConfiguration component role + rendering implementation + platform implementation (to get the data from a wiki page) + Admin UI (add a new "JIRA Macro" section in addition to the "JIRA" one )
• Introduce a new "parameters" parameter for the JIRA macro
• Naming rule for the parameters:
  • "source.<hint>.*" for JIRADataSource parameters
  • "field.<hint>.*" for JIRAFieldDisplayer parameters. For example for the link label mentioned above: "field.url.label"
  • "display.<hint>.*" for JIRADisplayer

User will use the "parameters" macro parameter only when he wants to override the default configuration. Similar to what we should also do for field definitions for JIRA-12 and JIRA-13. Example usage for this case:

{{jira id="xwikiorg" fields="..." parameters="field.url.label='Lien', ..."}}...{{/jira}}