added css variable based themes

drugsTone-build/drugsTone.js

drugsTone-build/styles.css

drugstone-test.html

src/app/app.module.ts

...p/components/analysis-panel/analysis-panel.component.scss

...nents/analysis-panel/drug-table/drug-table.component.scss

...nents/analysis-panel/prot-table/prot-table.component.scss

src/app/components/task-list/task-list.component.html

src/app/components/task-list/task-list.component.scss

src/app/pages/explorer-page/explorer-page.component.html

src/index.html

src/styles.scss

src/theme.css

src/theme.scss