Use PkgTestSuite for CI (#131)

This standardizes the CI process between JuliaFEM packages

test/run_lint.jl

@@ -1,17 +0,0 @@
-# This file is a part of JuliaFEM.
-# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
-
-using Lint
-using Base.Test
-
-results = lintpkg("JuliaFEM")
-if !isempty(results)
-    info("Lint.jl is a tool that uses static analysis to assist in the development process by detecting common bugs and potential issues.")
-    info("For this package, Lint.jl report is following:")
-    display(results)
-    info("For more information, see https://lintjl.readthedocs.io/en/stable/")
-    warn("Package syntax test has failed.")
-    @test isempty(results)
-else
-    info("Lint.jl: syntax check pass.")
-end