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/guvas12d/CMakeLists.txt

@@ -1,5 +1,5 @@
 upm_mixed_module_init (NAME guvas12d
-    DESCRIPTION "Guvas12d analog UV sensor"
+    DESCRIPTION "Analog UV Sensor"
     C_HDR guvas12d.h
     C_SRC guvas12d.c
     CPP_HDR guvas12d.hpp

src/guvas12d/guvas12d.hpp

@@ -35,11 +35,12 @@ namespace upm {
     /**
      * @library guvas12d
      * @sensor guvas12d
-     * @comname Grove UV Sensor
+     * @comname Analog UV Sensor
      * @altname GUVA-S12D UV Sensor
      * @type light
      * @man seeed
      * @con analog
+     * @web http://wiki.seeed.cc/Grove-UV_Sensor/
      * @kit eak
      *
      * @brief API for the GUVA-S12D UV Sensor