enable pod install with loacl sdk

Podfile

@@ -3,6 +3,19 @@ platform :ios, '9.0'
 source "https://gitlab.linphone.org/BC/public/podspec.git"
 source "https://github.com/CocoaPods/Specs.git"
 
+def basic_pods
+	if ENV['PODFILE_PATH'].nil?
+		pod 'linphone-sdk', '~> 4.1-221-g241bbf9'
+		else
+		pod 'linphone-sdk', :path => ENV['PODFILE_PATH']  # loacl sdk
+	end
+	
+	pod 'Firebase/Core'
+	pod 'Fabric', '~> 1.9.0'
+	pod 'Crashlytics', '~> 3.12.0'
+	pod 'Firebase/Performance'
+end
+
 target 'latestCallsWidget' do
   # Uncomment the next line if you're using Swift or would like to use dynamic frameworks
   use_frameworks!
@@ -24,11 +37,7 @@ target 'liblinphoneTester' do
   use_frameworks!
 
   # Pods for liblinphoneTester
-  pod 'linphone-sdk', '~> 4.1-221-g241bbf9'
-  pod 'Firebase/Core'
-  pod 'Fabric', '~> 1.9.0'
-  pod 'Crashlytics', '~> 3.12.0'
-  pod 'Firebase/Performance'
+  basic_pods
   
   target 'liblinphoneTesterTests' do
     inherit! :search_paths
@@ -42,11 +51,7 @@ target 'linphone' do
   use_frameworks!
 
   # Pods for linphone
-  pod 'linphone-sdk', '~> 4.1-221-g241bbf9'
-  pod 'Firebase/Core'
-  pod 'Fabric', '~> 1.9.0'
-  pod 'Crashlytics', '~> 3.12.0'
-  pod 'Firebase/Performance'
+  basic_pods
 
   target 'linphoneTests' do
     inherit! :search_paths

README.md

@@ -61,7 +61,7 @@ Build the linphone-iphone :
 - pod install
 It will download the linphone library from our gitlab repository so you don't have to build anything yourelf.
 
-Then open linphone.xcworkspace file (instead of linphone.xcodeproj) to install the app.
+Then open linphone.xcworkspace (instead of linphone.xcodeproj) to install the app.
 
 # Testing the application
 
@@ -83,11 +83,10 @@ See: https://developer.apple.com/library/archive/documentation/DeveloperTools/Co
 
 -Follow the instructions in the linphone-sdk/README file to build the SDK.
 
--Edit in the Podfile, change the way to pod linphone-sdk. 
- * For example, replace "pod 'linphone-sdk', '~> 4.1-221-g241bbf9'" by "pod 'linphone-sdk', :path => "<path to linphone-sdk-ios>"".
-
 -Rebuild the project:
- * pod install
+ * env ENV[PODFILE_PATH]=<path to linphone-sdk-ios> pod install
+ 
+-Then open linphone.xcworkspace (instead of linphone.xcodeproj) to install the app.
 
 # Quick UI reference