phases: add a list of names usable by the phase command
This is useful in TortoiseHg for example, which has until recently just added
all names in the `phasenames` list to the context menu that changes the phase.
The ones not supported by the command would just error out.
# See http://EditorConfig.org for the specification
root = true
[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true
[*.t]
indent_size = 2
indent_style = space
trim_trailing_whitespace = false