Update Project and CIs to Julia 1.4

[abelsiqueira]

I'm removing support for NLPModels < 1.2 because I'm updating to support 1.2 and this package it not released yet.

[codecov[bot]]

Codecov Report

Merging #15 into master will decrease coverage by 0.62%. The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #15      +/-   ##
==========================================
- Coverage   66.66%   66.03%   -0.63%     
==========================================
  Files           3        3              
  Lines          54       53       -1     
==========================================
- Hits           36       35       -1     
  Misses         18       18

Impacted Files	Coverage Δ
src/qpmodel.jl	66% <0%> (-0.67%)	:arrow_down:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 3c0ac0e...99c8418. Read the comment docs.

[abelsiqueira]

Thanks