Fixes several errors

What's Changed

• The efficiency of lignite and oil power plants were incorrectly calculated because premise could not identify the fuel input.
• The Simapro files could no longer be imported in Simapro 9.5.
• Add conda-forge badge and update install instructions by @m-rossi in #94

New Contributors

• @m-rossi made their first contribution in #94

Full Changelog: v.2.0.1...v.2.0.2