TropFishR 1.2

New features
  - Due to more efficient matrix computations ELEFAN is 2-4 times faster as before
  - missing seed values were added in ELEFAN_GA()
  - `plot.lfq()` allows plotting relative frequencies, this is
  in particular useful in cases where one sampling time has a large number of samples
  - `plot.catchCurve()` allows plotting results according to length rather
  than relative age. This can be done with the argument `xaxis`.
  - lfq plot can be used to plot 2 different lfq data sets; this allows to visually compare the two data sets
  - `lfqModfiy()` allows combining two different lfq data sets. This
  might be interesting when different fleets are investigated separately
  - possible to define and plot multiple regression lines
  in the catch curve analysis
  - length converted catch curve can account for the seasonalized VBGF
User-visible changes
  - better control over graphical devices with par(),
  when par() defined the default settings are not used
  - growth parameters can now be added to lfq lists as "par" elements, this
  is convenient as it is in line with the results of the ELEFAN methods
Documentation
  - new vignette with a short description of lfq data and
  how to import lfq data into R 
  - updated tutorial vignette
  - more informative error and warning messages for many functions
  - document with news and changes about package version was added
Bug fixes
  - crash report of ELEFAN_GA with interactive sessions (Rstudio) fixed
  and more stable on windows
  - plot.catchCurve() was not displaying the regression line, but
  a straight line from the first to last point of the chosen interval
  - restructering of lfq data was not in line with FiSAT implementation
  - fixing bug in handling of leap years
  - when merging lfq data with another list using c() one has to reassign
  the class "lfq" to the merged object, this has been added in the tutorial
  - beep sound was causing R crashes on windows computers and was therefore removed