First attempt at graph-traversal paths.
Update README.md
Fixed two issues with itsdb.py:
* table rows are now properly being written with newlines
* default values are cast as strings so they can be escaped
Merge branch 'master' of https://github.com/goodmami/pydelphin
Initial commit for Doe branch.
Incremental Doe update.
[incr tsdb()] character replacements should be ordered.
doe.py now uses [incr tsdb()] profiles.

This change allows [incr tsdb()] profiles to be used as input
to doe.py with the `-i` option. The `--select`, `--apply`, and
`--filter` options can customize how the profiles are read. These
changes resulted in improvements to the `itsdb.TsdbProfile` class
such that it can take multiple filters or applicators that are
used when reading a table (with the read_table() method).
Incremental work toward outputing profiles.
Rebased to master, added note about filters.
Filtering [incr tsdb()] profiles now cascades.

For example, filtering item:i-id will affect any tables that use item:i-id (e.g. parse), even transitively (e.g. result). This does not work in reverse---filtering parse:i-id does not also filter the item table (but DOES filter any downstream (depending on parse's key parse-id), such as result or rule).
Fixed up the cascading filtering mechanism.

There was a variable scoping bug in the construction of key filters in delphin/itsdb.py, which is now fixed. This results in a more robust cascading filter. There is not the --cascade-filters option, which, if true, filters all dependent tables. For this commit, I also removed the Stag-like commands, as they are currently broken. They will be re-added when they are ready.
Uncommented lines and relations file bug fixed.

Some remaining lines related to the --list option and configuration file variables (like source_grammar, etc.) were left uncommented, leading to some errors. Also, the --relations filename argument was opened as a file instead of just checking for the file existence, which caused an error. Both have been fixed.
Output profiles not required; applicators bugfix.

Output profiles are not necessary for operations like --select, but the code was having validation errors when an output profile was not specified. This is no longer the case.

Also, the __init__ function of TsdbProfile had an incorrect identifier for the applicators, which caused an error. This has been fixed.
Update README.md
Moved codecs, and added EDS output.

The *MRS codecs in delphin.codecs have been moved to delphin.mrs.
Future codecs should just go in their respective packages (like
delphin.mrs, or delphin.tdl, etc.). Case in point, I added a codec
for Elementary Dependency Structures to delphin.mrs.eds. Currently
it only implements dump() and dumps(), since it can't easily be
loaded to a full Xmrs. It also doesn't output the "triples" ED
format, nor does it mark disconnected subgraphs (e.g. "Nearly" in
"Nearly every dog barked."). Of these last two issues, the former
is a missing feature, the latter is a bug (which requires a new
feature, like xmrs.is_connected(nodeid) or something).
Merged master back to SimpleDmrs branch.
Moving simpledmrs module to delphin.mrs package.

Codecs were moved to their respective packages, rather than delphin.codecs, in the master branch, so I'm making things consistent in this branch.
MRS Lnk creation no longer crashes on empty RELS.

MRSs assumed non-empty RELS lists for making a CFROM and CTO value for the MRS. Now, if there are no RELS, it uses the defaults of -1, -1.