Replace Nmass PSMC model with Xija version

The following changed files are necessary for the new model to run.

Comparison of the test plots produced by the proposed and flight versions of pyger yield expected results.

pyger.py:
Remove import of twodof and characteristics files.
Remove definition of n_times since this isn't used anywhere.
Replace Nmass model code with Xija model code.
Set initial pin1at temp to initial 1pdeaat temp - 10.5 C.

psmc_spec.json:
Add file.

cosntraint_models.json:
Add fep_count to list of state_cols in psmc model.
Remove 1pin1at from list of msids in psmc model.

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Remove code no longer necessary, fix some minor bugs.

__init__.py:
Fix bug in help statement for "--max-1dpamzt" argument.
Replace "minus_z" with "minus_yz" in plot title geneneration code.

make_sim_inputs.py:
Remove import of Ska.DBI since it is not used anywhere
Remove import of characteristics file since it is not used as of this release.
Remove definition and references to "psmc_powers" since it is no longer used as of this release.

characteristics.py:
Remove file; this is no longer used with migration of PSMC model to Xija framework.

twodof.py:
Remove file; this is no longer used with migration of PSMC model to Xija framework.

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Update version to 0.5

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Update documentation to match current capability and usage.

doc/index.rst:
Add new models to documentation (minus-z is not mentioned except when showing command output since it will be removed in the future).
Show current output from commands used in examples.
Update code exampes to reflect current usage.
Update images.

doc/constraints.png:
Update with more recent version.

doc/dwells_2011_month.png:
Removed file, to be replaced in a separate commit.

examples/plot_by_month.py:
Update code to reflect current models and usage.
Call functions explicitly from matplotlib.pyplot so this example can be run from outside of ipython.

pyger/pyger.py:
Update merge_dwells1 function defaults to reflect common current usage, and to be consistent with documentation.




Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Make minor change to index.rst, add example plot png file.

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Update constraints.png with a new version using more simulations.

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Fix PeP8 with autopep8, make minor clarification in doc/index.rst

Signed-off-by: Matthew Dahmer <matthew.dahmer@gmail.com>
Update plot_by_month.py

Update comment on first line to reflect correct year
Fix conf.py path insert so docs build from local repo package
Merge pull request #5 from sot/add_psmc_xija

Add PSMC xija model and remove twodof PSMC model