General fixes for v2.0.0a1

[wk9874]

Lots of fixes for v2.0.0 found when testing the integrations repo against v2.0.0a0, and also addressing some issues found by Andrew. Main bug fixes are:

• Added created, started and end times for offline runs: Offline sender doesn't provide created, start or end times for fast runs #683
• Fixed offline artifact upload to use full file path instead of trying to recreate it: Saving artifacts doesn't work in offline mode #682
• Loosens the numpy requirement to >2.0.0 so that it can work with Tensorflow
• Make timestamp validation in utilities consistent with all others: log_metrics gives an exception when timestamp is specified #702
• Adds missing runtime attribute to RunObject
• Added new from_run method to Artifacts which uses /run/run_id/artifacts endpoint so that category has an effect and improved tests to catch this case: Category parameter has no effect in client.get_artifacts_as_files #687
• Fixed hierarchical artifact download, so that if you save nested artifacts they will be retrieved in subdirectories
• Removed setLevel from dispatch so that DEBUG logs arent spammed to console: DEBUG log messages from factory being spammed to console #689
• Added randomname generator into offline mode runs with no name provided: Offline mode breaks if no run name provided #699
• Fixed link printed to the console by removing /api from the end: Link printed to console is incorrect #690
• Suppressed errors if code tries to upload a traceback to events log once termination is called: Cannot upload error message to run, termination called #698

Don't merge until other PRs have gone in, and double check that from_run method is in Artifacts before merging due to some cherry picking mistakes