Merge 'file ls' and 'ls' commands

[magik6k]

ipfs file ls is this command which duplicates half of the normal ls functionality and missing the other half (plus seems to be a bit outdated).

IMO we should just remove it and merge it's functionality with the normal ls

(first commit which mentions it: 434871b)

[kjzz]

Hey @magik6k, if you did't finish this work and offical team decide to do this , i am willing to help you do for this. It also will help me learn more about ls and unixfs. Thx a lot.

[overbool]

@magik6k currently, some go-unixfs functions are refactoring: #5217 and ipfs/go-unixfs#3.

so, I think this issue could wait until the issues mentioned above are fixed. However, it is also a good choice to solve this issue firstly.

WDYT?

[kjzz]

The reason why i did not fix it immediately is this featuren may cause breanking.Also the issue should influence js-ipfs.So this issue need to be considered carefully by offical team,

[overbool]

@kjzz I don't have any experience with js-ipfs. If this issue will influence js-ipfs, maybe it should be handled with care.

[overbool]

@magik6k In my own view, it's better to fix #5502 firstly.