Otlet

- add release date and time to CLI return
- add notifier if version has been yanked

- [API] remove DeprecationWarning from otlet.packaging.version.LegacyVersion
- since this is an indexing program, we need to retain LegacyVersion for properly searching/displaying package versions that do not conform to the PEP 440 standard
- [API] add otlet.packaging.version.etc for extra version-related operations
- [API] rename 'otlet.api.get_full()' to 'otlet.api.get_package()'
- [API] merge 'otlet.api.get_release_full()' functionality into 'otlet.api.get_package()'

- [API] add packaging.version submodule into project (located at: 'otlet/packaging/version')
- [API] docs changes

- [CLI] add some color and bold text to warning/note labels
- [CLI] add items to CLI output
- Documentation URL
- Homepage URL
- Maintainer
- [CLI] add --urls option
- returns list of relevant URLs for given package
- [CLI] add extra info to --releases
- [CLI] add '-lt' and '-gt' options for use with --releases
- [API] change PackageObject.info.version from `str` to `Union[packaging.version.Version, packaging.version.LegacyVersion]`
- [API] change PackageObject.releases from `Dict[str, URLReleaseObject]` to `Dict[Union[packaging.version.Version, packaging.version.LegacyVersion], URLReleaseObject]`
- [API] docs changes

- [API] add PackageVulnerabilitiesObject
- [CLI] add vulnerability warning if any are present for a given release
- [CLI] add --vulnerabilities option
- returns paginated list of vulnerabilities, if any, for a given release
- [CLI] add --releases option
- returns list of all available release versions
- [API] add documentation
- [API/CLI] rename modules
- otlet.http -> otlet.api
- otlet.otlet -> otlet.cli
- [API] fix Optional class params to store NoneType if blank str

- fix bug where packages with blank releases would raise an error