[MRG] Add line_overlap and boxes_flow to LAParams

[Arnie97]

I need to lower the line_overlap parameter to arrange punctuation marks on correct lines, hence this pull request.

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As an example:

The correct result, after setting line_overlap=0.25:

　接京沪、津秦、津霸客专高速、京津联
络、武津、天津西、津霸客专线

The incorrect result produced when line_overlap=0.5, which is the default value provided by pdfminer. Note the punctuations were placed on a different line:

　接京沪　津秦　津霸客专高速　京津联
　　　　、　　、　　　　　　、
络　武津　天津西　津霸客专线
　、　　、　　　、

[codecov-io]

Codecov Report

Merging #219 (0dee385) into master (7709e58) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #219   +/-   ##
=======================================
  Coverage   88.35%   88.35%           
=======================================
  Files          14       14           
  Lines        1571     1571           
  Branches      358      358           
=======================================
  Hits         1388     1388           
  Misses        128      128           
  Partials       55       55           

Impacted Files	Coverage Δ
camelot/utils.py	82.05% <ø> (ø)

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[claire-peters]

Hey, @vinayak-mehta, is there a reason this change hasn't been merged? I'm eager to see this happen because I also need to be able to tweak the line_overlap and boxes_flow parameters, and it seems like a relatively minor fix - not counting the documentation, it's six lines of code.

[vinayak-mehta]

Sorry for the late reply here.

Closing and reopening to see if checks run again.

[vinayak-mehta]

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