doc: Scrubbed ALL sensor library descriptions

In an effort to clean-up and standardize UPM library
documentation, this commit updates (and in most cases,
unifies) the CMake description string AND CXX header
@comname string.

Strings were taken from datasheets when possible, spelling
mistakes were addressed, copy/paste errors where fixed,
Title Case was used, etc.

    * Tested/updated/added @web tags
    * Added/updated invalid sensor images
    * Added/updated @man tags, added missing manufacturers

Signed-off-by: Noel Eck <noel.eck@intel.com>

src/groveo2/CMakeLists.txt

@@ -1,5 +1,5 @@
 set (libname "groveo2")
-set (libdescription "GroveO2 oxygen concentration sensor module")
+set (libdescription "Oxygen (O2) Concentration Sensor")
 set (module_src ${libname}.cxx)
 set (module_hpp ${libname}.hpp)
 upm_module_init(mraa)

src/groveo2/groveo2.hpp

@@ -37,7 +37,7 @@ namespace upm {
   /**
    * @library groveo2
    * @sensor groveo2
-   * @comname Grove O2 Sensor
+   * @comname Oxygen (O2) Concentration Sensor
    * @type gaseous
    * @man seeed
    * @con analog