Fix a few typos and clarify policy

Specify that both upper and lower bounds are accepted.

README.md

@@ -13,13 +13,13 @@ _StrongVersions_ enforces a strict policy on your `Gemfile` requirements:
 * The pessimistic `~>` operator must be used for all gem requirement definitions.
 * If the gem version is greater than 1, the requirement format must be `major.minor`, e.g. `'~> 2.5`'
 * If the gem version is less than 1, the requirement format must be `major.minor.patch`, e.g. `'~> 0.8.9'`
-* An upper bound can be specified as long as a valid pessimistic version is also specified, e.g. `'~> 8.4', '< 8.6.7' # Bug introduced in 8.6.7`
+* A lower/upper bound can be specified as long as a valid pessimistic version is also specified, e.g. `'~> 8.4', '< 8.6.7'`
 * All gems with a `path` or `git` source are ignored, e.g. `path: '/path/to/gem'`, `git: 'https://github.com/bobf/strong_versions'`
 * All gems specified in the [ignore list](#ignore) are ignored.
 
-Any gems that do not satisfy these rules will be included in included in the _StrongVersions_ output with details on why they did not meet the standard.
+Any gems that do not satisfy these rules will be included in the _StrongVersions_ output with details on why they did not meet the standard.
 
-The benefit of applying this standard is that, if all gems follow [Semantic Versioning](https://semver.org/) always be relatively safe to run `bundle update` to upgrade to the latest compatible versions of all dependencies. Running `bundle update` often brings advantages both in terms of bug fixes and security updates.
+When all gems in a `Gemfile` follow this convention it SHOULD always be safe to run `bundle update` (assuming all gems adhere to [Semantic Versioning](https://semver.org/)).
 
 ![StrongVersions](doc/images/strong-versions-example.png)