title: Convert coordinate systems using SQLGeometery
body: <p>One of my shape files looks like this:</p>
  
  <pre><code>POLYGON (
    -91.513078999999991 36.970298, 
    -87.01993499999999 36.970298, 
    -87.01993499999999 42.508337999999995, 
    -91.513078999999991 42.508337999999995, 
    -91.513078999999991 36.970298)
  </code></pre>
  
  <p>Another file is using SRID 3857:</p>
  
  <pre><code>POLYGON (
    -10033572.109485552 4727287.954831399, 
    -10033571.708142675 4727287.954831399, 
    -10033571.708142675 4727288.1439229213, 
    -10033572.109485552 4727288.1439229213, 
    -10033572.109485552 4727287.954831399)
  </code></pre>
  
  <p>Assuming I can figure out which coordinate systems are being used, how do I convert from one format to the other?</p>