Fixed all the problem reported by interfacer (replace with the interface when is possible)

These warnings were suppressed by putting the type in the name of the method

.golangci.yml

@@ -25,7 +25,6 @@ linters:
   - goconst
   - gocyclo
   - govet
-  - interfacer
   - lll
   - maligned
   - megacheck

arduino/cores/cores.go

@@ -111,9 +111,10 @@ func (platform *Platform) GetOrCreateRelease(version *semver.Version) (*Platform
 	return release, nil
 }
 
-// GetRelease returns the specified release corresponding the provided version,
+// GetReleaseRelaxedVersion returns the specified release corresponding the provided version,
 // or nil if not found.
-func (platform *Platform) GetRelease(version *semver.Version) *PlatformRelease {
+func (platform *Platform) GetReleaseVersion(version *semver.Version) *PlatformRelease {
+	// use as an fmt.Stringer
 	return platform.Releases[version.String()]
 }
 
@@ -124,7 +125,7 @@ func (platform *Platform) GetLatestRelease() *PlatformRelease {
 	if latestVersion == nil {
 		return nil
 	}
-	return platform.GetRelease(latestVersion)
+	return platform.GetReleaseVersion(latestVersion)
 }
 
 // GetAllReleasesVersions returns all the version numbers in this Platform Package.

arduino/cores/packagemanager/download.go

@@ -81,7 +81,7 @@ func (pm *PackageManager) FindPlatformReleaseDependencies(item *PlatformReferenc
 
 	var release *cores.PlatformRelease
 	if item.PlatformVersion != nil {
-		release = platform.GetRelease(item.PlatformVersion)
+		release = platform.GetReleaseVersion(item.PlatformVersion)
 		if release == nil {
 			return nil, nil, fmt.Errorf("required version %s not found for platform %s", item.PlatformVersion, platform.String())
 		}

arduino/cores/packagemanager/package_manager.go

@@ -288,7 +288,7 @@ func (ta *ToolActions) Release(version *semver.RelaxedVersion) *ToolReleaseActio
 	if ta.forwardError != nil {
 		return &ToolReleaseActions{forwardError: ta.forwardError}
 	}
-	release := ta.tool.GetRelease(version)
+	release := ta.tool.GetReleaseRelaxedVersion(version)
 	if release == nil {
 		return &ToolReleaseActions{forwardError: fmt.Errorf("release %s not found for tool %s", version, ta.tool.String())}
 	}

arduino/cores/tools.go

@@ -62,9 +62,9 @@ func (tool *Tool) GetOrCreateRelease(version *semver.RelaxedVersion) *ToolReleas
 	return release
 }
 
-// GetRelease returns the specified release corresponding the provided version,
+// GetReleaseRelaxedVersion returns the specified release corresponding the provided version,
 // or nil if not found.
-func (tool *Tool) GetRelease(version *semver.RelaxedVersion) *ToolRelease {
+func (tool *Tool) GetReleaseRelaxedVersion(version *semver.RelaxedVersion) *ToolRelease {
 	return tool.Releases[version.String()]
 }
 
@@ -86,7 +86,7 @@ func (tool *Tool) LatestRelease() *ToolRelease {
 		return nil
 	}
 
-	return tool.GetRelease(latest)
+	return tool.GetReleaseRelaxedVersion(latest)
 }
 
 // latestReleaseVersion obtains latest version number.