libSUFR Code

system.f90: use ioStat and ioMsg similarly to intrinsic Fortran functions

* system.f90: use ioStat and ioMsg similarly to intrinsic Fortran functions:
* like e.g. read(..., iostat=ioStat, iomsg=ioMsg)
* in subroutines file_open_error(), file_open_error_quit(), file_read_error(), file_read_error_quit()
* rename dummy variables status and message where possible

date_and_time: make pure procedures elemental (search and replace)

Add functions (s)isinf(), (s)isnan() and (s)isnormal() to check for Infor NaN

* Add functions:
+ isinf(), sisinf() - variable is +/- Infinity (double/single precision)
+ isnan(), sisnan() - variable is not a number (NaN) (double/single precision)
+ isnormal(), sisnormal() - variable is normal: not +/- Inf or NaN (double/single precision)

Optics/reflectance_transmittance(): optionally return angle of transmittance

Constants: add c2k (Celcius to Kelvin) and pc_gr (mean gravitational acceleration on Earth's surface)

Add LICENSE to root. Update copyright.

date_and_time: add function jd2year(). Constants: add r2mas, mas2r

* date_and_time: add function jd2year():
* convert JD to decimal year (e.g. 2000.0)

* constants: add r2mas, mas2r:
* convert radians to milliarcseconds and vice versa
* + rr2mas,rmas2r (single-precision)

Optics/reflectance_transmittance(): take into account absurd incidence angles

Optics: add subroutine reflectance_transmittance()

* Optics: add subroutine reflectance_transmittance():
* compute the reflectance for a transition from one medium to another
* optionally, compute the transmittance, and the polarised R/T components

getopt: make optCount a public module variable

* getopt: make optCount a public module variable:
* also, start counting at 0 and +1 at beginning of routine, iso end