Issue #1164: Fixed failing test_pycuda_example.

Removed unnecessary #includes from generated cuda code.
Merge pull request #1171 from abalkin/headers-not-found

Issue #1164: Fixed failing test_pycuda_example.
Fix crash tensor.roll(Var, iscalar) reported by Jeremiah Lowin.
Added link to Nicolas Pinto ebuild on gentoo.
Fix memory leak in HostFromGpu when allow_gc=False!

fix gh-1154
Merge pull request #1173 from nouiz/fix_crash_roll

Fix crash tensor.roll(Var, iscalar) reported by Jeremiah Lowin.
Minor rewriting in doc
Typo fixes
Typo fix