Fix build scripts (#668)

Authored by snowleopard on Sep 1 2018, 1:50 PM.

Description

Fix build scripts (Trac #668)

  • Delete scripts relying on global package database
  • Simplify Cabal build script
  • Simplify the default build script
  • Fix path
  • Invoke the build script from GHC root
  • Switch to newer Cabal
  • Don't disable Cabal output
  • Add build.cabal.bat