Reduce console output

[peastman]

When I import opemmtools, it immediately produces a bunch of output to the console.

Warning on use of the timeseries module: If the inherent timescales of the system are long compared to those being analyzed, this statistical inefficiency may be an underestimate.  The estimate presumes the use of many statistically independent samples.  Tests should be performed to assess whether this condition is satisfied.   Be cautious in the interpretation of the data.

****** PyMBAR will use 64-bit JAX! *******
* JAX is currently set to 32-bit bitsize *
* which is its default.                  *
*                                        *
* PyMBAR requires 64-bit mode and WILL   *
* enable JAX's 64-bit mode when called.  *
*                                        *
* This MAY cause problems with other     *
* Uses of JAX in the same code.          *
******************************************

That means every script or program that uses openmmtools immediately begins by filling the console with warnings, whether or not it uses the timeseries module or pymbar. It's annoying for your own scripts, and a serious problem for programs meant to be used by other people. Could these warnings be eliminated, or at least made so they only get printed if you use the features they relate to?

[mikemhenry]

We can lazy load the pymbar package which is where this warning is coming from.