Fix comment and keyword typos.

Corrections for a few typos I noticed while working on Issue #1.

Author: process1183

adafruit_sgp30.py

@@ -69,7 +69,7 @@ def __init__(self, i2c, address=_SGP30_DEFAULT_I2C_ADDR):
 
         # get unique serial, its 48 bits so we store in an array
         self.serial = self._i2c_read_words_from_cmd([0x36, 0x82], 0.01, 3)
-        # get featuerset
+        # get featureset
         featureset = self._i2c_read_words_from_cmd([0x20, 0x2f], 0.01, 1)
         if featureset[0] != _SGP30_FEATURESET:
             raise RuntimeError('SGP30 Not detected')

setup.py

@@ -52,7 +52,7 @@
     ],
 
     # What does your project relate to?
-    keywords='adafruit sensiron sgp30 gas sensor ec02 tvod i2c hardware micropython circuitpython',
+    keywords='adafruit sensiron sgp30 gas sensor eco2 tvoc i2c hardware micropython circuitpython',
 
     # You can just specify the packages manually here if your project is
     # simple. Or you can use find_packages().