Clarify wording on specs versions

CONTRIBUTING.md

@@ -80,6 +80,7 @@ An RFC in the Explainer stage captures a described problem or partially-consider
 An explainer does not need to meet any entrance criteria. An Explainer may be an issue or a pull request (though an illustrative pull request is preferable).
 
 #### Entrance criteria
+
 * A well defined problem or use case. 
 * Identification of potential concerns, challenges, and drawbacks.
 

docs/specs/composition.md

@@ -8,14 +8,15 @@
 
 ### Versioning Guidelines
 
-Tools implementing the Lottie specification SHOULD consider the following
+The Lottie specification version number uses a semantic versioning system,
+tools implementing the specification SHOULD consider the following
 guidelines:
 
-* Major version updates MAY contain breaking changes that are not compatible
+* Major version signal the possibility of breaking changes that are not compatible
 with previous versions of the specification.
-* Minor version updates typically add new functionality and SHOULD NOT
-contain breaking changes.
-* Patch version updates typically make minor changes or clarifiactions to
+* Minor version updates typically add new functionality but do not
+contain breaking changes for existing features.
+* Patch version updates typically make minor changes or clarifications to
 already existing functionality.
 
 #### Authoring Tools
@@ -28,8 +29,8 @@ major versions.
 
 #### Animation Players
 
-Players SHOULD determine what major versions they support and handle brekaing
-changes across supported major versions. Players SHOULD expect to handle
+Players SHOULD determine what major versions they support and handle breaking
+changes across supported major versions. Players SHOULD be able to handle
 animations that specify both newer and older versions of the Lottie
 specification and SHOULD issue a warning if: