Add support for Firefox Developer Edition

This also fixes a bug where we wouldn't install to Chrome on Linux if
Firefox wasn't also present.

Closes #48
Updates #51

truststore_darwin.go

@@ -17,7 +17,6 @@ import (
 )
 
 var (
-	FirefoxPath         = "/Applications/Firefox.app"
 	FirefoxProfile      = os.Getenv("HOME") + "/Library/Application Support/Firefox/Profiles/*"
 	CertutilInstallHelp = "brew install nss"
 	NSSBrowsers         = "Firefox"

truststore_linux.go

@@ -15,7 +15,6 @@ import (
 )
 
 var (
-	FirefoxPath         = "/usr/bin/firefox"
 	FirefoxProfile      = os.Getenv("HOME") + "/.mozilla/firefox/*"
 	CertutilInstallHelp = `apt install libnss3-tools" or "yum install nss-tools`
 	NSSBrowsers         = "Firefox and/or Chrome/Chromium"

truststore_nss.go

@@ -17,8 +17,13 @@ var (
 )
 
 func init() {
-	_, err := os.Stat(FirefoxPath)
-	hasNSS = !os.IsNotExist(err)
+	for _, path := range []string{
+		"/usr/bin/firefox", nssDB, "/Applications/Firefox.app",
+		"/Applications/Firefox Developer Edition.app",
+	} {
+		_, err := os.Stat(path)
+		hasNSS = hasNSS || !os.IsNotExist(err)
+	}
 
 	switch runtime.GOOS {
 	case "darwin":
@@ -32,9 +37,7 @@ func init() {
 		hasCertutil = !os.IsNotExist(err)
 
 	case "linux":
-		_, err := os.Stat(nssDB)
-		hasNSS = hasNSS && !os.IsNotExist(err)
-
+		var err error
 		certutilPath, err = exec.LookPath("certutil")
 		hasCertutil = err == nil
 	}