Implementation for SWS scale (#33)

* Draft implementation for SWS scale

* Update go.mod

* Revert "Update go.mod"

This reverts commit 760fb8c427.

* Renaming to AllocSwsContext and remove ChangeResolution this should handled by users

* update example to use new name and remove ChangeResolution

* Follow scaling example from libav, update readme, improve sws

Change scaling example to an similar libav example
Update readme
Add func to UpdateScalingParameters
Rename AllocSwsContext to SwsGetContext
Using a type for scaling algos/flags

* Fix Errors in scale example

* Review Changes

Now using sws context flags
Restructer sws context and adding ned simpler methods to update the ctx
Update the example
Update the test

* Correctly handle error for buffer alloc in PrepareDestinationFrameForScaling

* Add more getter and setter for sws

Get/Set source w,h,pixfmt
Get/Set dst w,h,pixfmt
Get/Set sws flags

* Adding resolution get/set

* Use CachedContext when updating sws ctx

* Review changes

Reorder flags, and update them
# Update Example
Use renaming function to create sws context
Clean up
Use new framdata image funcs
# Sws scale context
New way to update the context
Use sws_scale_frame instead of sws_scale
Reordering funcs for get and set
# Sws sclate context flag
Add "Flag" for algo name
# Update sws test

* fix fmt error args bug

* Review Changes

Simpfy sws update
Use c.int for sws flags
update test

internal/cmd/flags/main.go

@@ -21,13 +21,14 @@ var list = []listItem{
 	{Name: "CodecHardwareConfigMethod"},
 	{Name: "Dictionary"},
 	{Name: "FilterCommand"},
-	{Name: "FormatContextCtx"},
 	{Name: "FormatContext"},
+	{Name: "FormatContextCtx"},
 	{Name: "FormatEvent"},
 	{Name: "IOContext"},
 	{Name: "IOFormat"},
 	{Name: "Packet"},
 	{Name: "Seek"},
+	{Name: "SoftwareScaleContext"},
 	{Name: "StreamEvent"},
 }