0.3.5

Added features:

• Command 'list' now shows packages and subpackages in alphanumerical order (issue #34)
• Command 'list' now shows all the available packages in the remote with the option -r, with no filters whatsoever (issue #37)
• Commands 'add' and 'update' now accepts a version specifying, e.g. $ pypickup add numpy==1.8 (issue #36)
• Commands 'add' and 'update' now accepts a requirements-like file (like the one outcomed by 'pip freeze') (issue #31)