Awickert, this article (Deformation (mechanics) has the objective, which you propose, of discussing in one article the concept of deformation (strain). And from here to link to other, more detailed, articles about Finite and Infinitesimal deformation theories.
If some of the material that was in the article strain tensor is not included please bring it back into this article or the Infinitesimal strain theory article.
Renaming the Infinitesimal strain theory, and Finite strain theory into infinitesimal strain and finite strain it is something I have to think about. My first impression is that the word "theory" is broader than just saying "strain".