how to migrate from ionic 1 to ionic 2 ?
There is no real migration path as they are fundamentally different.
Here is some information from Ionic: http://ionicframework.com/files/Ionic2Migration.pdf
Is there any plugin in ionic which will migrate our ionic1 code to ionic2 ?
No. It is completely different.
Nope, this is not possible. Read the PDF I linked, what is described in there is the only upgrade path.
Thanks for the info.
Is there anything in ionic 1 which we can re-use in ionic 2 ?
CSS, Assets, general template “structure” maybe.
I really advice you to go through the PDF I linked, it shows this on an example project.