Merge pull request #1 from Rutherther/feat/split-logic-respect-dry

Split file_parser logic

fix: parse entity and architecture only at beginning

The file parser treated entity and architecture keywords
at beginning and end of architecture equally, and expected
an identifier afterwards. This identifier is not required.

The change made the parser always go past the end of the entity
or architecture declaration.

chore: fix formatting using fmt

feat: split logic of context and comment tokens

Respect DRY for file_parser. So far, the file parser did not
just parse the file, it also parsed custom comment "tokens"
and managed a context. This is not the responsibility of the
parser. The parser should just parse the file and return
the parsed parts.

feat: Add parser and tcl generator