Add sparql and Semantic Web icons (#890)

* Add SPARQL and Semantic Web

* Update README

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Co-authored-by: Terence Eden <edent@users.noreply.github.com>

images/svg/semantic_web.svg

@@ -0,0 +1,10 @@
+<svg xmlns="http://www.w3.org/2000/svg" role="img" viewBox="0 0 512 512"
+aria-label="Semantic Web"><path
+d="m0 0H512V512H0"
+fill="#fff"/><path
+fill="#86ba0c"
+d="M273.4 106.5c-19.3-8.7-15.5-7.6-15.5-7.6L97.2 164.8l160.7 78.3s12.4-5.2 32.4-14.9C388.4 180.6 409.6 64 409.6 64s-24.4 93-136.3 42.5Z"/><path
+fill="#ef7c00"
+d="M239 448 89 367V200L239 276"/><path
+fill="#bd1789"
+d="m273 448 150-81V200l-150 76z"/></svg>

images/svg/sparql.svg

@@ -0,0 +1,12 @@
+<svg xmlns="http://www.w3.org/2000/svg" role="img" viewBox="0 0 512 512"
+aria-label="SPARQL"><path
+d="m0 0H512V512H0"
+fill="#fff"/><path
+id="a" fill="#0C479C"
+d="M386.944 198.125c-3.8972.7349-14.4175 20.8193-12.4967 59.332 1.2281 24.6254 3.2578 43.6942 17.7911 56.4609H334.8096c14.9418-13.014 15.9758-40.6409 15.8291-56.5351-.235-25.4549-6.9725-46.3612-14.1397-54.6718a71 71 44 1150.445-4.586"/><path
+id="b" fill="#fff"
+d="M312.5 94.6c20.8-22.6 54-26 74-7.2-15.7-10-35-3.6-49.8 5.7 10.9 11-.8 29-14.7 24.1-5.3-1.9-9 2.3-10.2 3.8-9.8 18.5-10.2 38.1-.4 47.5-19.6-18.8-19.2-51.6 1.1-73.9"/><use
+href="#a" transform="rotate(120,290,258)"/><use
+href="#a" transform="rotate(-120,290,258)"/><use
+href="#b" transform="translate(-205 130)"/><use href="#b"
+transform="translate(11 248)"/></svg>