#7498 - Drop legacy PEAR stuff

[ztroudi]

Fix : #7498

[greg0ire]

This one is a work in progress, will be tested under Windows. Some questions arose, like how are people to run the doctrine binary under Windows? Should they use the bat file or should they use bin/doctrine directly, in which case, the bat file should be removed entirely? Can anyone give some context about this bat file? Also, we found a https://github.com/doctrine/orm/blob/master/bin/doctrine-pear.php file, should it be removed too?

[beberlei]

@greg0ire many good questions I also have some more ;)

• Doesn't ocmposer automatically generate bat files now on Windows? Do we even need this file at all anymore?

I would target 2.8.x for this cleanup not master

[derrabus]

Closing in favor of #9661 and #9662.