Fix makefile typos.

makefile

@@ -9,13 +9,16 @@ ifneq ($(ANDROID_DEVICE),)
 ADB_DEVICE_ARG=-s $(ANDROID_DEVICE)
 else
 # You can think of NR as the line number (sort of) here (it's actually "number of records seen so far").
-# We have to do $$1 is the make-escaped version of $1, which is the first column.
+# We have to use $$1 as the make-escaped version of $1, which is the first column.
 # So, this is just taking row 2, column 1 from 'adb devices'; we do row 2 to skip the header line.
 ADB_DEVICE_ARG=-s $(shell adb devices | awk 'NR==2{print $$1}')
 endif
 
 all: install
 
+# The help target here reads the makefile (MAKEFILE_LIST is the name of the file `make` ate), looks for
+# lines matching commands, and pulls out the command name and anything following it containing a comment
+# starting with #@.
 .phony: help
 help: #@ Makefile help.
 	@grep -E '^[a-zA-Z_-]+:.*?#@ .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS=":.*?#@ "};{printf "%-16s %s\n", $$1, $$2}'
@@ -37,7 +40,7 @@ install: #@ Install the build to all devices.
 	@$(GRADLE) installDebug
 
 .phony: run
-run: stop #@# Run the build, engage the logger.  Must have been installed first.
+run: stop #@ Run the build, engage the logger.  Must have been installed first.
 	@adb $(ADB_DEVICE_ARG) shell monkey -p $(BINNAME) 1
 	@sleep 1 # TODO: loop until pidof gives us a valid number
 	@adb $(ADB_DEVICE_ARG) logcat --pid=`adb $(ADB_DEVICE_ARG) shell pidof $(BINNAME)`