NEMOSIS

• Fixed #20 where NEMOSIS couldn't access bid data after March 2021 because AEMO changed the format in which the data was published. Thanks @dawkinsmw for helping put together the methodology for extracting the data from the new format. Note with the format change there is still a window of missing data which includes March 2021, the 1st of April 2021, and the first 4 hrs of the 2nd of April.
• Added the rebuild option to the dynamic_data_compiler function, this forces NEMOSIS to rebuild feather or parquet cache files from the raw CSV data. This is useful if you want to add extra columns to the data cache, as described here: https://github.com/UNSW-CEEM/NEMOSIS#accessing-additional-table-columns