Skew-T Diagram Missing Features

[christinaholtNOAA]

These are some leftover aspects to addressed, as specified by Craig's prototype and updated as of PR #25

• Labels for adiabats and mixing ratio lines.
• Add 850 and 250 hPa lines
• Plot parcel profile only when greater than T
• Change colors of hodograph levels and add legend.
• Use earth-realtive wind conversions

[christinaholtNOAA]

After PR #35, items remaining:

• Add 850 and 250 hPa lines
• Plot parcel profile only when greater than T
• Use earth-realtive wind conversions