removing dataset and yamlmodelrunner

just prepping for when we can merge this in!
really honing in on the formatting of log messages

also checking for when the number of alternatives goes down to zero
small logging edits
Fix docstring indentation in regression.py.

Also use print function so my linter stops complaining at me.
Save final simulation data under "final/" namespace in HDFStore.
Initial docs on the UrbanSim simulation framework.

[ci skip]
Document class attributes in urbansim.sim.simulation

[ci skip]
Make _TableSourceWrapper a private class.
print the time that models take to run - everyone should be aware, right?
Merge branch 'master' into remove-dataset-mdlrunner
logging year and model with the time it took
Merge pull request #89 from synthicity/full-run-testing

Full run testing
Merge pull request #88 from synthicity/sim-docs

Simulation framework documentation
Add "getting started" section with install instructions

[ci skip]
Merge pull request #90 from synthicity/install-docs

Install docs
Run SF simulation as part of tests.
Merge pull request #91 from synthicity/sf-test

Run SF simulation as part of tests
Fix an infinite loop while merging tables

While writing docs on broadcasts I ran across a broadcast graph
configuration that caused an infinite loop in merge_tables.
I've made things more robust by better standardizing the data type
that gets passed to _next_merge and added a test case for that
graph configuration.
Merge pull request #93 from synthicity/merge-tables-bug

Fix an infinite loop while merging tables

While writing docs on broadcasts I ran across a broadcast graph
configuration that caused an infinite loop in merge_tables.
I've made things more robust by better standardizing the data type
that gets passed to _next_merge and added a test case for that
graph configuration.
Add docs on table broadcasts