docs: Make README improvements (#15)

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README.md

@@ -1,10 +1,52 @@
 # better_test_reporter
 
+[![Build status](https://github.com/Betterment/better_test_reporter/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/Betterment/better_test_reporter/actions/workflows/ci.yml?query=branch%3Amain)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Maintenance](https://img.shields.io/badge/Maintained%3F-yes-green.svg)](https://GitHub.com/Betterment/better_test_reporter/pulse)
+
+
 ## Introduction
 
-This is an application/library heavily inspired by [dart-junitreport](https://github.com/TOPdesk/dart-junitreport) and [dart-testreport](https://github.com/TOPdesk/dart-testreport). It takes what was done in those two packages and brings them under a single umbrella, updates to null-safety, and various code style improvements.
+This is an application/library heavily inspired by [dart-junitreport](https://github.com/TOPdesk/dart-junitreport) and [dart-testreport](https://github.com/TOPdesk/dart-testreport). It takes what was done in those two packages and brings them under a single umbrella, updates to null-safety, and makes various code style improvements.
 
 The purpose of this package is three-fold:
 - Firstly, it provides models by which output from the [test json reporter](https://github.com/dart-lang/test/blob/master/pkgs/test/doc/json_reporter.md) can be decoded.
 - Secondly, it provides a processor that will take a full json report from the test json reporter and generate a more developer-friendly report model structure that is agnostic to the protocol version of the test json reporter.
-- Thirdly, it is a command-line application that can be used to take in a full json report from the test json reporter and generate a junit XML report(usable by many CI tools)
+- Thirdly, it is a command-line application(`report_to_junit`) that can be used to take in a full json report from the test json reporter and generate a junit XML report(usable by many CI tools)
+
+## Getting Started
+
+In order to start using the `report_to_junit` command, install the latest `better_test_reporter` as a global packages via [pub.dev](https://pub.dev).
+
+```bash
+pub global activate better_test_reporter
+```
+
+### Options
+Details on all options for `report_to_junit` can be found by running `report_to_junit --help`
+```
+> report_to_junit --help
+-i, --input        the path to the 'json' file containing the output of 'pub run test'.
+                   if missing, <stdin> will be used
+-o, --output       the path of the to be generated junit xml file.
+                   if missing, <stdout> will be used
+-b, --base         the part to strip from the 'path' elements in the source
+                   (defaults to "")
+-p, --package      the part to prepend to the 'path' elements in the source
+                   (defaults to "")
+-t, --timestamp    the timestamp to be used in the report
+                   - 'now' will use the current date/time
+                   - 'none' will suppress timestamps altogether
+                   - a date formatted 'yyyy-MM-ddThh:mm:ss' will be used as UTC date/time
+                   - if no value is provided
+                       - if '--input' is specified the file modification date/time is used
+                       - otherwise the current date/time is used
+-h, --help         display this help text
+```
+
+## Misc
+
+### Differences from original implementation in `dart-junitreport` and `dart-testreport`
+
+1. When generating the XML for a problem during a test, `dart-junitreport` had a special case for only one problem occurred. The multiple problem case also handled the case for a single problem. We found the special case for a single problem unneeded and a little buggy, so it was removed in `better_test_reporter`.
+2. When parsing the test reporter json into a report, `dart-testreport` set tests as not hidden if they encountered any problems while running. In `better_test_reporter`, the hidden attribute on a test will be purely based on whether the test was explicitly hidden based on the `TestDoneEvent` json. That said, we maintained the hidden behavior for the output junit xml by shifting that decision out of the report and up to whatever consumes the report.