TODO

[ ] Vignette:
*** Optimization of params B084--Tohoku

[ ] Functions:
*** Diffusivity/Transmiss/Storativ calculations

[ ] Add environment to store global or default constants
*** options()?

[ ] Frequency units of output should be consistent with frequency units of input
    (currently only Hz is returned)
*** open_well_response [X]
*** well_response [ ]
    		  *** Ensure utilities (eg kitplot) wont hickup

[ ] Fix so that complex response is always output, with new method to convert
    to Amp/Phs (for 'wrsp')
*** open_well_response [X]
*** well_response [ ]

[ ] Datasets:
*** PBO-PP well information (and calculated sensing volumes)