* Make emitters produce a pair (dict, Item), in order to preserve the output
at print_data (dict is used if no custom format is specified, Item otherwise).
* Simplify the handling of the paths, printed at the top of print_data. The
path key is removed from the dict entirely and fetched from the Item.
* Add custom output formatting via a format string to InfoPlugin. The command
accepts a formatting string via the "-f" parameter, which is handled by its
CommonOptionsParser and applied during print_data().
* Modify the emitters in order to include an Item into the list of fields, that
is formatted according to the format string if specified.
* Add an argument to allow the user to choose if track lengths are displayed as
raw floats or using a human-readable form (mm:ss), defaulting to human-readable
form.
Should fix#1433. The problem now was that we were freeing the string memory
that Python expected to be managing in a string object held by the `uri`
variable. Now, we do a silly dance to copy the memory out of the buffer
returned by the library and return that instead.
This avoids some round-tripping problems with types (such as ScaledInt) that
are not represented in strings with 100% fidelity. It also makes the syntax
nicer when editing numbers and booleans: they no longer appear to be
needlessly surrounded by quotes in the YAML.
I hadn't quite realized before that the user could also change the *keys* to
be non-strings too! This also prevents against that by just reinterpreting
everything as strings.
We now ask for a trinary edit/apply/cancel confirmation *after* showing the
updates. This lets you decide whether you're done based on a "preview" of the
changes and keep editing if they don't look right.
Removed three prompts:
1. The "really edit?" prompt. If you don't want to edit, you can just not make
any changes.
2. The "done?" loop. This seems unnecessary; we'll confirm afterward anyway.
3. The YAML checker. This removal could indeed make things inconvenient, since
your changes get thrown away if you make a YAML mistake. For the moment,
simplicity is taking priority.
