Version log stdDEB-TKTD package for BYOM

Version BETA 0.1 (19 Nov. 2021) not released on the web page

- First test version of the package without TKTD module.

Version BETA 0.2 (22 Nov. 2021) not released on the web page

- Various changes to the call_deri embryo section to make it work robustly. Starting point for the embryo calculations is now the analytical solution for a foetus without maintenance, rather than E0 from AmP implied properties. This should work better when re-fitting basic DEB parameters. Also added an event for embryos: when e goes below 0.1, the run is terminated. Otherwise, the embryo will probaby just continue shrinking till the end of the time vector.
- Allowed interp1 to also extrapolate when e is outside of the range of the table values for E0 vs. e.

Version BETA 1 (25 Nov. 2021) not released on the web page

- Changed the event for embryos: when e goes below l (instead of some absolute threshold), the run is terminated. 
- Allowed interp1 only in derivatives to also extrapolate when e is outside of the range of the table values for E0 vs. e. In call_deri, an error message when attempting to extrapolate is probably best, as something is going wrong then.
- First test version of the package with TKTD module.

Version BETA 2 (8 Dec. 2021) not released on the web page

- When fitting maturity levels, there is the possibility that values of EHp or EHj are tried that are lower than EHb. In theory, puberty before birth is a possibility. However, in the code this is problematic. For now, I solve this by returning from call_deri immediately when EHp or EHp is lower than EHb, with an empty output. This will force transfer to return minloglik = +inf, so the optimisation knows that there is no point to look there.
- Added Weibull mortality coefficient "a" to to all folders. When this parameter is fixed to 1, we have the normal constant hazard rate. Values other than 1 result in Weibull mortality.

Version Beta 3 (13 Jan. 2022) first release on the web page

- An error crept into call_deri for starting at a specified L0>Lb. The rB was not calculated anymore (to estimate a reasonable time vector for the simulation, this is now fixed.
- Added a piece of code to allow a zero-variate data point for Lm. This may help avoid unrealistic size when re-fitting some parameters.
- Allows glo.E0_calc to have multiple rows, one for each data set. Also added a third option: the egg costs can now also be calculated using f=1 always.
- When using a specified L0, the code now throws an error if that L0 cannot be reached with the current values for the basic parameters. This prevents it getting stuck. However, this does not work yet for the case of acceleration, since we don't know beforehand what the maximum length will be.
- The EPx calculation for certain profiles turned out to be very slow. This related to the hazard rate becoming extremely high in the 'rough exploration' of the MF range, in cases where there is no effect on one of the endpoints. This is solved by maximising the hazard rate to 111 d-1, which implies 99% mortality in 1 hour.
- This package is aimed at TKTD analyses, but there was an initial package stdDEB without that module. This package is now provided in a sub-folder. It may be handy for other types of analysis.

Version Beta 4 (21 April 2022)

- The hazard rate in derivatives is maximised to 111 d-1, which implies 99% mortality in 1 hour. This avoids the system becoming stiff under extreme parameter settings/forcings. This value assumes that all times are entered in days!
- Tiny change in call_deri. When using an exposure scenario (with make_scen) and NOT breaking up the time vector (glo.break_time=0), call_deri sets smaller step size for the ODE solver. This makes sure that no concentration switches are missed. I now make an exception for very simple scenarios (Tev of length 2), as it is not needed and makes the solver rather slow. 
- Included the option to have body size data as wet weight, rather than physical length. This also involves the initial value: the parameter par.L0 is now interpreted as initial wwt when setting glo.len=0. From birth to reaching L0, it is assumed that par.f holds.
- More options for using zero-variate data, such as egg wet or dry weight.
- Renamed reference length glo.Lm_ref to glo.Lwm_ref to make it clearer that this is a physical length and not a volumetric one. For the same reason, par.L0 is now renamed to par.Lw0.

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Errors spotted and things that will be changed in future releases:
- ...