v0.0.6

CompositeGrids v0.0.6

Diff since v0.0.5

Merged pull requests:

• remove dependence on the parent module (#26) (@kunyuan)
• Modulize chebyshev (#27) (@iintSjds)
• bug fix. allow arbitrary grid to take only one grid point (#28) (@iintSjds)
• Mc tools (#29) (@iintSjds)