Specify document search parameter as HTTP params

[archiloque]

An implementation for #720 , feedbacks are welcome.

I'm still doing some tests.

Notes so far:

• I tried to share the code between the two ways of passing parameters, I moved the related code to docs-web/src/main/java/com/sismics/docs/rest/util/DocumentSearchCriteriaUtil.java to avoid making a mess of docs-web/src/main/java/com/sismics/docs/rest/resource/DocumentResource.java, at the end it's not too much new code.
• Moved docs-web/src/main/java/com/sismics/docs/rest/util/TagUtil.java from docs-core because it was not used outside of docs-web.
• I've renamed the simple search as simple search, so it's easier to distinguish between simple and full.
• Specified some parameters as optionals, even with other end points.
• Cleaning some code duplication between get and list for documents when generating the responses, as a consequence I added the file_id field to the get response because it was missing there but was in the list one, which did not make sense.

I wonder if all the cases exposed through the "textual API" make sense for a programmatic one, for example:

• at can be replaced by before and an after, should it be available?
• exposing several date formats, maybe the yyyy-MM-dd one should be enough?

What's your opinion ?

[jendib]

Looks good.

I agree that "at" and date formats other than "yyyy-MM-dd" could be removed to simplifiy. It should be the role of the caller to do those things with "before" and "after".

[archiloque]

@jendib thanks, I've updated the code accordingly

[jendib]

@archiloque Is this ready to merge?

[archiloque]

@jendib yes, I've done some integration tests and it seems to work