Feature/standard tooling

Created by: jsturdy

• Adds a information to the README
• Adds a generic help target that is built based on the defined targets immediately preceeded by ## [@section] help message
• Removes some redundant intermediary targets
• Adds common variables that can be overridden in package specific makefiles
• Adds (un)install targets for standard packages as well as two variants (-pip, and -site) for python packages

testing

Tested against xhal, ctp7_modules, and gem-plotting-tools