This is the first GLESv1 tests.  GL_OES_draw_texture is a GLESv1
specific extension.

The tests are added to the newly created all_es1.tests.

Changes since v1:

 - rename the file name to oes_draw_texture.c
 - rename the static variable glDrawTexiOES to piglit_glDrawTexiOES
 - add all_es1.tests for this (and future) GLESv1 tests

Changes since v2:

 - Put the test in tests/spec/oes_draw_texture instead of tests/gles1.
 - Minor fixes to all_es1.tests

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>