added main and defined M_PI

Dependencies:   BNOWrapper

Revision:
0:0f12b8c4d5f1
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.gitignore	Tue Jul 16 16:37:37 2019 +0000
@@ -0,0 +1,4 @@
+.build
+.mbed
+projectfiles
+*.py*