add gitignore and update readme

.gitignore

@@ -0,0 +1 @@
+example

README.md

@@ -1,13 +1,13 @@
 ## gtest
-gtest is a simple, single-header C testing library. 
+gtest is a simple, single-header C testing library for GNU/Linux.
 
 gtest runs each test in separate child process, so bugs that cause segmentation
 faults do not interrupt testing. It also does not print test stdout and stderr
 unless a test failed. This means that log outputs do not clutter output.
 
 ## Example
 This example code can be found in [`example.c`](./example.c) and can be run
-simply with `gcc example.c -o example`.
+simply with `gcc example.c -o example && ./example`.
 
 ```c 
 #define _GNU_SOURCE
@@ -20,6 +20,11 @@ main(void)
 		gassert(1 + 1 == 2);
 	}
 
+	gtest_ignore = 1;
+	gtest("Test that is ignored") {
+		gassert(0);
+	}
+
 	gtest("Test that will fail") {
 		gassert(1 + 1 == 3);
 	}
@@ -34,16 +39,16 @@ The output of this test (minus the fancy colors) is:
 
 ```
 ✓ PASS Test that will pass
+IGNORE Test that is ignored
 ✗ FAIL Test that will fail
 
-
 2 tests were run:
 ✓ PASS: 1
 ✗ FAIL: 1
-
-
+IGNORE: 1
 
 --------- stdout of Test that will fail ---------
 
 --------- stderr of Test that will fail ---------
 example: 	 Assert failed: "1 + 1 == 3"
+```