Consistent table-like input for PyGMT functions/methods

[seisman]

xref #1318 and #2722.

When working on the tutorial for table inputs in PyGMT, I realized that the behavior of table inputs are still inconsistent.

Generally speaking, there are two different ways to pass tables into PyGMT: via data or via x/y/z. For data, it can be a file, a pandas.DataFrame, a 2-D NumPy array. Currently, some functions/methods don't support x/y/z. We need to check all methods/functions to make sure they have consistent behavior for table inputs.

This issue is a central place to track the progress. Here is the list of methods/functions that we may need to check:

• binstats
• blockm*
• contour [data or x/y/z]
• filter1d
• grdtrack
• histogram
• info
• legend
• meca
• nearneighbor
• plot
• plot3d
• project
• rose [data or length/azimuth]
• select
• sph2grd
• sphdistance
• sphinterpolate
• surface [data or x/y/z]
• ternary
• text
• triangulate [data or x/y/z]
• velo
• wiggle [data or x/y/z]
• xyz2grd [data or x/y/z]
• x2sys_cross