This is a changelog for the dev branch of FLEXPART (see flexpart.eu)
Created by Petra Seibert, 8 June 2018 to document and explain in detail why I changed what.

* makefile, 2018-06-08
  ========

1) Add a GPL3+ License statement, author statement, version information. Prudent to do that, not harmful.

2) There are already two sections, one for gfortran4 and one for gfortran5.
Both have NILU-specific paths. So let us have at least one generic and put that in front.

2) Compiler options. 
2.1) For the regular compile, we don't want -g (debug symols)
2.2) We don't need -m64, on a 64bit platform this is default
2.3) Remove $(USER) as it is never defined
2.4) Remove -Warray-bounds, this is default.
2.5) Add -fbacktrace in the commented-out part, it is important for debugging
2.6) Change comment for VPATH, explain what this directive does
2.7) Added some explanation of options as comment.  Maybe expand later.

Notes and questions:
1. Would be nice to have a debug version also for serial code.
2. Would be nice to have "as fast as possible" option (thought it might be machine-dependent ...)
3. What is the purpose of -Warray-bounds ? Is it relevant for Fortran? I think if there is a compile-time array-bound violation this would be a hard error?

* FLEXPART.f90
  ========

Update version string!

* readcommand.f90
  ===========

Correct misleading error message (replace "open" by "write to")
Improve error messages: combine pathname+filename, remove unaligned closing ###
Let STOP say in which subroutine we are stopping
Some minor changes

* verttransform_ecmwf.f90 PS 2018-06-13
  ===================

1) Remove some of commented out testing stuff
2) Fix indenting in the init if block
3) Code layout improvement
4) Change name of loops to represent the index
5) Fix ticket:140 Introduce a new way of establishing the reference position
   for the vertical grid. Also correct a minor bug in the calculation
   of height (array assignment where it was not intended)
6) Add back the SAVE attribute to INIT, just to be sure
7) Bring some more code under the IF (INIT) block
8) make some annotations
   [minor modification PS 2018-06-25]

* com_mod.f90  PS 2018-06-13
  =======
  
  correct the comment for nmixz

* verttransform_nest.f90 PS 2018-06-17
  ===================
1) insert proper boundaries for implied loops in array expressions
  (fixes bug annoted by ESO in 2016)
2) Code layout improvement
3) Change name of loops to represent the index
4) make some annotations

* verttransform_ecmwf.f90 PS 2018-06-25
  ===================

1) Some code layout improvement in the first part
2) Fix ticket:140 Introduce a new way of establishing the reference position
   for the vertical grid. Also correct a minor bug in the calculation
   of height (array assignment where it was not intended)
3) Add back the SAVE attribute to INIT, just to be sure



* checking type (EC/GFS) of grib files PS 2018-06-26
  ===================
replaced the CTBTO code by shorter & simper code with proper license  

Affected files:

calcmatrix.f90
calcpar.f90
calcpar_nests.f90
check_gribfile_mod.f90
convmix.f90
detectformat.f90
FLEXPART.f90
FLEXPART_MPI.f90
getfields.f90
getfields_mpi.f90
obukhov.f90
richardson.f90
timemanager.f90
timemanager_mpi.f90