fixing plot discharge

[mcekiz]

mm.plot_specific_discharge(spd) has depreceated, and it is not plotting. flopy documentation advised me to use .get_specific_discharge first, then use .plot_vector. I added them.
Regards

[mcekiz]

I removed plot_discharge and used plot_vector in 1st and 3rd plots. Time unit was given, so I added time unit to transient model, and added it to ax title.

[mcekiz]

1. mm.plot_specific_discharge was not working, I fixed them.
2. riv_data = gwf.riv_0.stress_period_data.array[0] was giving error, it can't find riv_0, fixed it.
3. There is no RIV_0, so it can not remove, turned to riv_1
4. SFR pakdata has no entry for rno, turned to ifno.
5. MAW pakdata has no enty for wellno, turned to ifno.
6. MAW connection data has no entry for wellno, turned to ifno.
7. Fixed typo in THEIM.
   It still has warnings that I didn't touch:

1. OPTIONS BLOCK VARIABLE 'UNIT_CONVERSION' IN FILE 'mv.sfr' WAS DEPRECATED
   IN VERSION 6.4.2. SETTING UNIT_CONVERSION DIRECTLY.
2. NONLINEAR BLOCK VARIABLE 'OUTER_HCLOSE' IN FILE 'mv.ims' WAS DEPRECATED
   IN VERSION 6.1.1. SETTING OUTER_DVCLOSE TO OUTER_HCLOSE VALUE.

[mcekiz]

1. I added label to model-actual result comparison.
2. In this part :
   quant = df[4].quantile(qthresh)
   We calculate quantile value lower than qthresh. I changed explanation accordign to that, added some comments for clarification.