Quad gpu fix

[zsteve]

This PR fixes type issues that prevent quadreg from running with CuArrays, and adds a test for that setting.
Also fixes a bug with the Armijo step search which I found for certain inputs caused the solver to get stuck.

[coveralls]

Pull Request Test Coverage Report for Build 1176317897

• 12 of 12 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 97.671%

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Totals
Change from base Build 1174249145:	0.02%
Covered Lines:	671
Relevant Lines:	687

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💛 - Coveralls

[codecov-commenter]

Codecov Report

Merging #121 (22b4f92) into master (d33f1cf) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #121      +/-   ##
==========================================
+ Coverage   97.65%   97.67%   +0.01%     
==========================================
  Files          13       13              
  Lines         682      687       +5     
==========================================
+ Hits          666      671       +5     
  Misses         16       16              

Impacted Files	Coverage Δ
src/quadratic_newton.jl	98.16% <100.00%> (+0.08%)	⬆️

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[devmotion]

Looks good to me!

[coveralls]

Pull Request Test Coverage Report for Build 1172918384

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 12 of 12 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 97.671%

---

Totals
Change from base Build 1165287400:	0.02%
Covered Lines:	671
Relevant Lines:	687

---

💛 - Coveralls