Emissions

[leonx075]

I have added a function "import_from_emissions" that is a modificiation of function "fetch_data_tables" by @eroten in the ghg.sp package. It allows to fetch tables from the emissions database.

[eroten]

Thanks for your PR, @leonx075! Take a look at the failing tests and modify as needed. There were a couple changes needed. Here is a summary

• Updated the function to use the most recent fetch_db_tables() from {ghg.sp}. This utilizes vector processing and is a bit more robust
• Added testing for import_from_emissions()
• Changed db_table_names to emissions_db_table_names. db_table_names is too vague for this context.
• Updated documentation
• Added you as a contributor
• Increment package date and version in DESCRIPTION
• Administrative stuff: added BugReports, Website in DESCRIPTION, fixed a couple typos