Added python script for parsing xml -> tsv or json.

[alvadia]

Added python script for parsing xml -> tsv or json.
First argument: from (example - dict.xml)
Second argument: to (example - dict.json)
Third argument: mode (example - json).

Sample format of tsv (' ' means space):
id \t root \t data \t extra \n
#header \t dictionary \t version \t revision \n
OpenCorpora \t dictionary \t <version_from_xml> \t \n
#lemmas lemma variants empty
[ \t ' ' <';'.join(attributes)> \t ' ' <';'.join(attributes)> [, ' ' <';'.join(attributes)>]* \t \n]*
#gramemes \t parent \t alias \t description \n
[ \t \t \t \n]*
#links \t from \t to \t type \n
[ \t \t \t \n]*

It requires much less space.
This script is a sample, it requires a .sh wrapper.

[alvadia]

#5