-"AttributeError: 'function' object has no attribute 'gridcorner'"

 -new output: full (t0,tau) Fstat map,
  if bands in those params are searched
 -one file per Doppler grid point

Closes #9

Previously, a check was done to ensure that all initial positions of the
walkers would yield a non -np.inf prior. This extends this to also check
the likelihood evaluations. The method is also simplified partially

Partially resolves issues in #6

The variable name was misleading and hence renamed

This renames the input sftfilepath to sftfilepattern and adds
documentation on how that should be used, i.e. a colon separated list of
wildstring or exact matches. In globbing for all matches, the colon
split is added in. sftfilepath is still used by `Writer` since
an exact path is known.

A search, based on Reinhard's J0537-6910 work, in which the search is
performed over F0 in a sliding window. Able to track changes in the
power and frequency of the signal.

Rather than starting with the fully-coherent Vsize, this now starts with
the input Nseg0 (i.e. from the SC search). and works back to Nseg=1.
The user is then left to check the V0 value and whether the search is
appropriate or not. Applies the idea to the follow-up example.

- Applies method to weak_signal method
- Adds methods to read/write setup files - this saves recalculating
  expensive optimial setups
- Simplifies notation and laoyout for generating setup and writing
  tables

Note that the dynamic injection is currently broken - it appears to only
be injecting the signal in one set of data

This adds a class to perform follow ups from semi-coherent to
fully-coherent using an MCMC search.

- Also changes the logic of the MCMC search to check for old data only
  in the run method.
- The nsteps argument exists for the MCMCFOllowUP, but is unused.
- Some work on the plot_walkers to allow for overplotting. It may be
  useful to use this for the usual calls as well so that we don't have
  an initial and walkers plot?

- Also changes the parameter vector in the normal fully coherent search
  to remove the tstart and tend. This is done by wrappin the
  run_computefstatistic_single_point in a compute_fullycoherent_det_stat
  function
- Removes theta0 from the saved data dict for the MCMCSearch
- Adds example usage of the semi-coherent search

Note - There appears to be some difference between the integration plot
and the output value. This may be related to the Riemann sum issue in
emcee itself. Eventually, we should have a case where we calculate the
Bayes factor directly and compare this.

Also adds ability to write transient data and a search script to show
the results of such a transient search