Squashed merge from upstream/master

commit 8dc281d654514c7bd27f115ceb294b30603671fb
Merge: 3262d51 07aceac
Author: Tim Otten <totten@civicrm.org>
Date:   Sun Oct 12 11:49:36 2014 -0700

    Merge pull request #19 from totten/master-usleep

    instance.yml locking - Change poll frequency. Allow override.

commit 07aceace79f13f4127332801c89264b2730c25bb
Author: Tim Otten <totten@civicrm.org>
Date:   Sun Oct 12 11:45:42 2014 -0700

    AMP_INSTANCES_TIMEOUT - Use env var to override timeout for acquiring lock on instances.yml

commit 81618f0e6f04cafb84c6816db729b75108e51798
Author: Tim Otten <totten@civicrm.org>
Date:   Sun Oct 12 11:36:23 2014 -0700

    PidLock - Poll in intervals of 10ms-200ms

commit 3262d51f8a2caed65acea7fbdedb0a80bf9ee970
Author: Tim Otten <totten@civicrm.org>
Date:   Thu Sep 18 00:13:17 2014 -0400

    composer.json - Loosen version constraints

Change-Id: Ib7c101d140fb9f7cd4425698d0b78fa49ee8c0b9
add .gitreview

Change-Id: I2bc154cceb5e668504d6890145d77ce5fe312f94