tweak gwinc keyword argument for plotting

Use 'plot' instead of 'fig', which can be confused with matplotlib
figure.

and update README

README.md

@@ -9,18 +9,19 @@
 
 `pygwinc` creates noise budgets based on detector descriptions
 provided in either .yml or .mat files (see below).  Once the detector
-description is loaded, the noise budget can be calculated with the
-`gwinc` command:
+description is loaded, the noise budget can be calculated and plotted:
 ```python
 >>> import gwinc
 >>> import numpy as np
->>> ifo = gwinc.load_ifo('aLIGO')
 >>> freq = np.logspace(1, 3, 1000)
->>> score, data, ifo = gwinc.gwinc(freq, ifo)
+>>> ifo = gwinc.load_ifo('aLIGO')
+>>> ifo = gwinc.precompIFO(ifo)
+>>> noises = gwinc.noise_calc(ifo, freq)
+>>> gwinc.plot_noise(ifo, noises)
 ```
-A convenience function to plot the resulting noise budget is included:
+Or the `gwinc` convenience function can be used to handle it all:
 ```
->>> gwinc.plot_noise(data)
+>>> score, data, ifo = gwinc.gwinc(freq, ifo, plot=True)
 ```
 
 

gwinc/gwinc.py

@@ -106,7 +106,7 @@ def noise_calc(ifo, f):
     return noises
 
 
-def gwinc(freq, ifoin, source=None, fig=False, PRfixed=True):
+def gwinc(freq, ifoin, source=None, plot=False, PRfixed=True):
     """Calculate strain noise budget for a specified interferometer model.
 
     Argument `freq` is the frequency array for which the noises will
@@ -117,7 +117,7 @@ def gwinc(freq, ifoin, source=None, fig=False, PRfixed=True):
     the detector to several potential gravitational wave
     sources.
 
-    If `fig` is specified a plot of the budget will be created.
+    If `plot` is True a plot of the budget will be created.
 
     Returns tuple of (score, noises, ifo)
 
@@ -146,7 +146,7 @@ def gwinc(freq, ifoin, source=None, fig=False, PRfixed=True):
     # --------------------------------------------------------
     # output graphics
 
-    if fig:
+    if plot:
         # Report input parameters
         if ifo.Optics.Type == 'DualCarrier_new':     #include the case for Dual carrier
             finesseA = 2*pi/ifo.Optics.ITM.TransmittanceD1