Create metadata (#133)

* Added migration for metadata table used to store a song's metadata

* Added comment for new table

* Added endpoint to create metadata

* Filling out code

* Changed type of duration in request

* Reorganizing code

* Changing metadata table to song

* Added TODO for data type discrepancy for the future

* Fix migration syntax error

* Added types to request

* Added environment variable for root directory:

* Moving keys to its own module

* Moved environement related code to its own module

* Added function to get root_directory

* Added endpoint to create song

* Minor fixes

* Added test and refactored tests

* Ironing out some kinks

* Resolved test issue

Turns out I was using the wrong id value

* Added env variable in workflow

* Added TODO

* Updated env variable

* clippy warning fixes

* Making sure date_created is populated when returneD

* Code cleanup

* Added TODOs

* Uncommenting tests

* Code formatting

.env.sample

@@ -1,6 +1,7 @@
 SECRET_MAIN_KEY=refero34o8rfhfjn983thf39fhc943rf923n3h
+ROOT_DIRECTORY=/home/icarus/mydata
 POSTGRES_MAIN_USER=icarus
 POSTGRES_MAIN_PASSWORD=password
 POSTGRES_MAIN_DB=icarus_db
 POSTGRES_MAIN_HOST=main_db
-DATABASE_URL=postgres://${POSTGRES_MAIN_USER}:${POSTGRES_MAIN_PASSWORD}@${POSTGRES_MAIN_HOST}:5432/${POSTGRES_MAIN_DB}
+DATABASE_URL=postgres://${POSTGRES_MAIN_USER}:${POSTGRES_MAIN_PASSWORD}@${POSTGRES_MAIN_HOST}:5432/${POSTGRES_MAIN_DB}