Adding center point to center column cylinder

[shimwell]

Proposed changes

Allows the CenterColumnShieldCylinder to be shifted vertically using a new argument called center_height which defaults to 0

The following image can now be made with code like this

import paramak
inner_vessel = paramak.CenterColumnShieldCylinder(
    inner_radius=3,
    outer_radius=3.3,
    height=5,
    color=(0,0,1),
    center_height=0
)

inner_vessel2 = paramak.CenterColumnShieldCylinder(
    inner_radius=3,
    outer_radius=3.3,
    height=5,
    center_height=-6,
    color=(1,0,0)
)

inner_vessel3 = paramak.CenterColumnShieldCylinder(
    inner_radius=3,
    outer_radius=3.3,
    height=5,
    center_height=6,
    color=(0,1,0)
)

r = paramak.Reactor([inner_vessel, inner_vessel2, inner_vessel3])
r.show()

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Code refactoring
• Documentation Update (if none of the other choices apply)
• New tests

Checklist

• Pep8 applied
• Unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

[codecov]

Codecov Report

Merging #33 (473fde5) into develop (da53362) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff            @@
##           develop      #33   +/-   ##
========================================
  Coverage    97.48%   97.48%           
========================================
  Files           73       73           
  Lines         4805     4814    +9     
========================================
+ Hits          4684     4693    +9     
  Misses         121      121           

Impacted Files	Coverage Δ
...ak/parametric_components/center_column_cylinder.py	100.00% <100.00%> (ø)

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[shimwell]

I don't have access to the method of making diagrams at the moment, so this PR really should have another parameter added to the diagram. I shall raise an issue so I don't forget