Keys of parsed JSON objects are escaped

[janikrabe]

The json::object::parse_pair function calls getQuoted to parse object keys. This means that object::_data contains JSON-escaped keys.

This causes the following issue in timewarrior as of GothenburgBitFactory/timewarrior@bdb28fa:

$ timew start '"a'
  Note: '"\"a"' is a new tag.
  Tracking "\"a"
    […]

$ timew stop
  Trying to decrement non-existent tag '"a'

After timew start is run, the tags.data file contains {"\"a":{"count":1}}. When running timew stop, libshared's parse_pair parses the key "\"a", but does not unescape it. This causes timewarrior not to find "a because the key is internally stored as \"a.

Possible solutions:

• Add a function to retrieve the key name in unescaped form and change timewarrior to use this function
• Change the internal representation of _data to store the unescaped string

Possibly related to GothenburgBitFactory/timewarrior#159