using store.Score to represent scores
starting a new format
script to convert a file to the new format added
there’s no .md file there
ScoresStore#_insert implemented
New format based on dicts implemented server-side

This doesn't break the compatibility with existing script versions.
However, it completely changes how the server is implemented and changes
the Web page a little bit.

Scores storage was previously implemented as a JSON file containing a
list of 3-elements lists: user, score and text. We now have a
`ScoresStorage` object which contains a bunch of dict-like `Score`
objects. This allows us to change the underlying storage without
breaking `ScoresStorage`’s interface, and to add other attributes on
scores like the upload date (which is not implemented right now).

This new version will automatically update any old storage file with the
new format, there’s no need to use `utils/updatefmt.py`, which will be
removed in a later commit.

While this commit marks a “working” version of the new storage, not all
tests have been adapted, and thus I won’t release the 0.0.7 version
right now.
Note about scores path in config.h added

By default, it seems that this version of Rogue save scores in the
current directory instead of a global one for the current user.
docs++
Score#__ne__ added, #dump removed
Score tests
useless script removed
versionadded doc annotations
ScoresStore#_insert return value fix

It was returning `None` when an element was inserted at any other place
than the last one.
ScoresStore#_add return False without user
BadScoreFormatException added
minor refactoring
ScoresStore tests added
merging 'json-objs' into 'master'