Docs of checksysodesol
Docs of dsolve for system of ODEs
merge conflicts
corrected errors in docs
corrected length of underline in doc
Merge pull request #7831 from KDMOE/docs_of_checksysodesol_and_dsolve

Docs of checksysodesol and dsolve
Added examples
Merge branch 'master' of https://github.com/sympy/sympy into vectordoc