Fixed json playlist parsing to avoid "warning" vpids
Apply JSON parsing fix to radio programmes
Suppress spurious errors in PVR log.
Switch to mediaselector 5 API, added --mediaselector

Default for vpid data is now mediselector 5 used on iPlayer site:

http://open.live.bbc.co.uk/mediaselector/5/select/version/2.0/mediaset/pc/vpid/<vpid>

atk and asn parameters not used - works without them at present, though
may be necessary in future.

--mediaselector=4 will revert back to previous API
Fix application of --whitespace to final file/path
Revert "Switch to mediaselector 5 API, added --mediaselector"

This reverts commit 2a23f8ebe5752844744fd6f90d0c188070e3230a.
Switch to mediaselector 5 API, added --mediaselector (2nd attempt)

Default for vpid data is now mediselector 5 used on iPlayer site:

http://open.live.bbc.co.uk/mediaselector/5/select/version/2.0/mediaset/pc/vpid/<vpid>

atk and asn parameters not used - works without them at present, though
may be necessary in future.

Modes not available with this change: wma, flashlow

--mediaselector=4 will revert back to previous API