Update README and add test example file

Author: neomantra

.vscode/launch.json

@@ -0,0 +1,16 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "gotf",
+            "type": "go",
+            "request": "launch",
+            "mode": "auto",
+            "program": "${workspaceFolder}/cmd/gotf",
+            "args": ["-g", "${workspaceFolder}/log.txt"], 
+        }
+    ]
+}

README.md

@@ -1,20 +1,102 @@
-# gotf - go time format
+# gotf - go time formatter
 
 `gotf` converts epoch times in inputs to human readable strings
 and outputs them to stdout.
 
 ```
 $ gotf --help
+usage:  ./gotf <options> [file1 [file2 [...]]]
 
+GOlang Time Formatter
+
+Reads text files, converting epoch times to human readable, outputting to stdout.
+
+10-digits are interpreted as seconds, 13 as milliseconds,
+16 as microseconds, and 19 as nanoseconds.
+
+If no filenames or only '-' is passed, stdin is processed.
+
+example:
+echo 1637421447 | gotf
+
+gotf -g log.txt | head
+
+  -b, --block           use block buffering (default: line buffering)
+  -d, --date            default format with '2006-01-02 15:04:05'
+  -f, --format string   golang Time.Format string (default: '15:04:05')
+  -g, --global          global match
+  -h, --help            show help```
+```
+
+----
+
+## Installing
+
+Binaries for multiple platforms are [released on GitHub](https://github.com/neomantra/gotf/releases) through [GitHub Actions](https://github.com/neomantra/gotf/actions).
+
+You can also install for various platforms with [Homebrew](https://brew.sh) from [`neomantra/homebrew-tap`](https://github.com/neomantra/homebrew-tap):
+
+```
+brew tap neomantra/homebrew-tap
+brew install gotf
+```
+
+----
+
+## Example Usage
+
+Raw log:
+```
+$ cat log.txt
+[1524241219] Time is on my side
+[1555777220] Yes it is
+[1587399621] A time in ecpoch millis: 1637419929123
+[1618935621] A time in ecpoch nanos: 1637419929123456789
+```
+
+Basic usage, piping from `stdin`:
+```
+$ cat log.txt | gotf
+[12:20:19] Time is on my side
+[12:20:20] Yes it is
+[12:20:21] A time in ecpoch millis: 1637419929123
+[12:20:21] A time in ecpoch nanos: 1637419929123456789
 ```
 
-# Building
+Date conversion:
+```
+$ gotf -d log.txt 
+[2018-04-20 12:20:19] Time is on my side
+[2019-04-20 12:20:20] Yes it is
+[2020-04-20 12:20:21] A time in ecpoch millis: 1637419929123
+[2021-04-20 12:20:21] A time in ecpoch nanos: 1637419929123456789
+````
 
+Global match, converting sub-second times:
 ```
-./build.sh
+$ gotf -gd log.txt
+[2018-04-20 12:20:19] Time is on my side
+[2019-04-20 12:20:20] Yes it is
+[2020-04-20 12:20:21] A time in ecpoch millis: 2021-11-20 09:52:09.123
+[2021-04-20 12:20:21] A time in ecpoch nanos: 2021-11-20 09:52:09.123456789
 ```
+----
+
+## Building
+
+This [simple script](./build.sh) will run unit tests and build the `gotf` binary for your plaftorm.
+
+```
+$ ./build.sh 
++ set -e
++ go test neomantra/gotf/internal/gotf
+ok      neomantra/gotf/internal/gotf    (cached)
++ go build -o gotf cmd/gotf/main.go./build.sh
+```
+
+----
 
-# Credits and License
+## Credits and License
 
 Copyright (c) 2021 Neomantra BV
 

log.txt

@@ -0,0 +1,4 @@
+[1524241219] Time is on my side
+[1555777220] Yes it is
+[1587399621] A time in ecpoch millis: 1637419929123
+[1618935621] A time in ecpoch nanos: 1637419929123456789