Initial commit

Part of the code copied from
https://wiki.archlinux.org/index.php/Dropbox#Multiple_Dropbox_Instances
Separate config from executable

Configuration is stored as specified in the XDG specification.
Users will add paths separated by a new line for each dropbox instances
that they want to make.
Fix bug that prevents dropbox from running gui

Since each of the instances are of a separate "home", the configuration will
differ from user. One case is running X. Each instances are blocked to be run
as a gui because they don't have .Xauthority which X uses for authenticating
local client. A symlink will do.
Fix whitespace issues
Supress std{out,err} and run in the background

Dropbox program does not fork so it needs to be run the background
so that other dropboxes will also be run.
Link .gtkrc-2.0 from home

This will maintain the consistency with the user chosen theme. Because
the dropboxes reside on different folder that they believe is $HOME, settings
will be not the same as the user.
Add README file
Create parent directory if it does not exist
Convert script to python and add some features

Dropbox installation may be located in a folder other than the default
(`$HOME/.dropbox-dist`) so a config for its path is added. Because of the
need to add this configuration, the format for the config file must be
change. JSON is chosen because data structure can be nested and its
availabilty. A Windows inf file style configuration is also considered but
does not support bare key-value entries.

There is no need for `$XDG_CONFIG_HOME/dropboxes` folder so this one is change
to a config file.