Ability to install modules using pip or conda (#380)

* Add support for pip and/or conda when installing modules * Fix display versions for environments (fixes #378) * Refactor installer to use the pip/conda module installer for installation of modules * Performance improvement of detecting virtual env and setting it (fixes #372) * Code refactor to ensure interpreter locators use the new DI framework * Fixes #266

Author: DonJayamanne

.vscode/tasks.json

@@ -66,30 +66,6 @@
  "fileLocation": "relative"
  }
  ]
- },
- {
- "label": "Hygiene (staged)",
- "type": "gulp",
- "task": "hygiene-staged",
- "problemMatcher": [
- "$tsc",
- {
- "base": "$tslint5",
- "fileLocation": "relative"
- }
- ]
- },
- {
- "label": "Hygiene (all)",
- "type": "gulp",
- "task": "hygiene",
- "problemMatcher": [
- "$tsc",
- {
- "base": "$tslint5",
- "fileLocation": "relative"
- }
- ]
  }
  ]
 }