Initial commit of SimpleDmrs.

Also a few small fixes here and there. There is also ongoing
work on delphin/mrs/path.py, so it should be considered
broken in this commit.
SimpleMRS now allows surface strings.

This is a non-canonical extension to the format. The surface string
can also have a Lnk value, and they both appear before LTOP. So
semantically these are all the same, but the first two will get
their "surface" value assigned the value of the string.

[ "A dog barked."<0:17> LTOP: h0 INDEX: e2... ]
[ "A dog barked." LTOP: h0 INDEX: e2... ]
[ LTOP: h0 INDEX: e2... ]

Inner escaped quotes are fine, so you can have:

[ "Pat said, \"hi.\"" LTOP: h0 INDEX: e2... ]
Removed a debugging statement.
Merge branch 'master' into SimpleDmrs
Initial commit of SimpleDmrs.

Also a few small fixes here and there. There is also ongoing
work on delphin/mrs/path.py, so it should be considered
broken in this commit.
SimpleMRS now allows surface strings.

This is a non-canonical extension to the format. The surface string
can also have a Lnk value, and they both appear before LTOP. So
semantically these are all the same, but the first two will get
their "surface" value assigned the value of the string.

[ "A dog barked."<0:17> LTOP: h0 INDEX: e2... ]
[ "A dog barked." LTOP: h0 INDEX: e2... ]
[ LTOP: h0 INDEX: e2... ]

Inner escaped quotes are fine, so you can have:

[ "Pat said, \"hi.\"" LTOP: h0 INDEX: e2... ]
Removed a debugging statement.
Merge branch 'SimpleDmrs' of https://github.com/goodmami/pydelphin into SimpleDmrs
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.