fix(naming): standardize casing

[RDWimmers]

• remove function from gef.geo and gef.expression
• post-processing of gef files now in CPT class. so xml and gef have the same post processing steps
• add class for vertical ref
• update plots, add hlines for groundwater level and predrilled depth

[coveralls]

Pull Request Test Coverage Report for Build 4415281325

• 188 of 214 (87.85%) changed or added relevant lines in 10 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.07%) to 87.352%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/pygef/gef/parse_cpt.py	64	65	98.46%
src/pygef/plotting.py	22	24	91.67%
src/pygef/shim.py	10	12	83.33%
src/pygef/gef/parse_bore.py	29	32	90.63%
src/pygef/bore.py	18	22	81.82%
src/pygef/common.py	12	16	75.0%
src/pygef/cpt.py	23	27	85.19%
src/pygef/broxml/resolvers.py	5	11	45.45%

Files with Coverage Reduction	New Missed Lines	%
src/pygef/bore.py	1	81.48%

Totals
Change from base Build 4373745149:	0.07%
Covered Lines:	960
Relevant Lines:	1099

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💛 - Coveralls