Ecape-parcel

Changed the value of sigma from 1.6 to 1.1 in accordance with the Matlab script and the final version of the paper.

Fixed slight buoyancy bug and updated documentation for custom storm motions.

Removed build artifacts to allow for easier addition to conda-forge.

**MAJOR FIX** - The updraft radius and entrainment rate formulas previously used were grossly incorrect. The correct formulas derived from ECAPE_FUNCTIONS are now used instead.

Mixed layer parcels now use the correct parcel origin. Mixed layer depth is now customizable in terms of both pressure and height.

Onboard CAPE computation can now be given custom integration bounds, allowing for easy computation of parameters such as 3CAPE and HGZ-CAPE using the parcels computed by this package.

Fixed an error in the computation of an abstract parameter related to the ECAPE values. Values should now much more closely match what would be expected from ECAPE parcel paths.

Added the option for custom T/Td/p/z values, primarily to aid in the use of custom mixed layer depths.